# SEO Madman

> Technical SEO news, original research, studies and free tools for search and AI answer engines, by Adam Hafez.

Editorial rules this publication holds itself to: every article opens with a 40 to 60 word direct answer,
carries three to five standalone key takeaways, and cites at least one primary source. Anything not supported
by a citable source is not published.

## News

- [Bing now asks some searchers to verify they are human](https://seomadman.com/news/bing-verify-you-are-human-check.md): Search Engine Roundtable reports Bing showing a verify-you-are-human checkbox before results. The trigger is unknown and the check was not reproduced.
- [OpenAI tests Sponsored Agents as a new ChatGPT ad format](https://seomadman.com/news/chatgpt-sponsored-agents-ads-test.md): OpenAI is testing Sponsored Agents: labeled conversations with a business agent that users start after clicking a ChatGPT ad, with select US advertisers.
- [Google Discover on desktop has disappeared, and Google is silent](https://seomadman.com/news/google-discover-desktop-missing.md): Search Engine Roundtable reports Discover no longer appears on desktop Google.com, with no explanation from Google. What is verified and what is not.
- [Google tests an AI Mode button in the results page search bar](https://seomadman.com/news/google-search-bar-ai-mode-button-test.md): Google is testing an AI Mode button in the search bar on results pages, not only the home page. The button is inconsistent and regular search still works.
- [Google Search profiles get new article cards and a lower bar](https://seomadman.com/news/google-search-profiles-update.md): Google cut the follower requirement for Search profiles to 10,000, added richer article views, and lets one account manage up to 10 profiles.
- [Google Analytics rolls out drag-and-drop custom dashboards](https://seomadman.com/news/ga4-custom-dashboards-launch.md): GA4 Dashboards let you drag dimensions and metrics onto a grid canvas, combining six chart types into one KPI page instead of separate reports.
- [Search Central Live returns to India for a Bengaluru date in October](https://seomadman.com/news/search-central-live-india-bengaluru.md): Google's Search Central team holds a free, one-day Search Central Live event in Bengaluru on October 30, 2026, its first India event since 2023.
- [Logging bug undercounted impressions in Search Console's AI report](https://seomadman.com/news/search-console-ai-report-logging-bug.md): A logging error cut reported impressions in Search Console's Generative AI report from August 13, 2026, Google says, with no real drop in visibility.
- [Google ranking volatility spikes sharply, no update confirmed](https://seomadman.com/news/september-15-ranking-volatility-spike.md): SEO chatter and rank-tracking tool activity spiked hard on 15 September 2026. Barry Schwartz suspects an update is starting; Google has confirmed nothing.
- [An unconfirmed September update hit big sites, then fully reversed](https://seomadman.com/news/september-update-reversed-days-later.md): Glenn Gabe tracked large sites dropping hard around September 3-4, 2026, then surging back on September 13. Google confirmed neither move.
- [Google documents its EEA-only aggregator and supplier units](https://seomadman.com/news/search-central-eea-aggregator-features.md): Google's September 2026 changelog documents aggregator units, supplier units and carousels: result formats limited to the EEA, South Africa and Turkiye.
- [Google splits site reputation enforcement along the EEA border](https://seomadman.com/news/site-reputation-policy-eea-split.md): From 30 August, a site reputation manual action changes results only outside the EEA. Inside it, the section is separated and left to rank on its own.
- [Bing reports how often AI answers cite your pages](https://seomadman.com/news/bing-ai-performance-citations.md): AI Performance in Bing Webmaster Tools counts citations in Copilot and AI answers, names the cited URLs, and shows the queries behind them.
- [Search Console now reports impressions from Google's AI features](https://seomadman.com/news/search-console-generative-ai-reports.md): Google added a generative AI performance report to Search Console, showing how often your pages surfaced inside AI Overviews, AI Mode and Discover.
- [Search Console now measures your TikTok, X and YouTube posts](https://seomadman.com/news/search-console-platform-properties.md): Platform properties let a creator see the queries that lead people to their Instagram, TikTok, X or YouTube content on Google Search and Discover.
- [The August 2026 spam update finished after three days](https://seomadman.com/news/august-2026-spam-update-completed.md): Google's August 2026 spam update ran from 18 to 21 August. Here is how to tell a spam-update drop from a core-update drop in your own data.
- [Google opens AI Mode ads to exact and phrase match keywords](https://seomadman.com/news/ai-mode-ads-rollout.md): Google confirmed on 4 September 2026 that exact and phrase match keywords can serve text ads in AI Mode, once reserved for AI Max and Performance Max.
- [Bing tests bolded HTTPS and snippets without site names](https://seomadman.com/news/bing-serp-display-tests-https-sitenames.md): Two separate September 2026 Bing tests change result snippets: one bolds the https segment of the URL, the other drops the site name line.
- [Publishers report Google News sitemap data stuck in Search Console](https://seomadman.com/news/google-news-sitemap-reporting-lag.md): Webmasters say the indexed pages report for their news sitemap has not moved since August 28, even though new articles are indexed and visible.
- [Google confirms AI Overviews now auto-expand on some queries](https://seomadman.com/news/ai-overviews-dynamic-expansion.md): Google confirmed on 28 August 2026 that AI Overviews can dynamically expand into a full, detailed answer for some queries, dropping the Show more control.
- [Google fixes Search Console favicon bug and a crawl stats data gap](https://seomadman.com/news/search-console-favicon-crawl-stats-bugs-fixed.md): Google fixed a bug replacing site favicons with a default globe icon in search results, and separately restored a two-day gap in Crawl Stats data.
- [ChatGPT Ads adds oCPC bidding and a product carousel](https://seomadman.com/news/chatgpt-ads-product-feeds.md): OpenAI added beta conversion bidding, dynamic URL macros and a multi-product carousel to ChatGPT Ads product feed campaigns on August 7, 2026.
- [Google's AI Mode terms for French publishers](https://seomadman.com/news/ai-mode-france-publisher-terms.md): Ahead of its French launch, Google told publishers it would offer an opt-out, separate AI traffic reporting, and neighboring-rights compensation.
- [Search Console configures Performance reports from a prompt](https://seomadman.com/news/search-console-ai-config-tool.md): AI-powered configuration turns a natural-language request into Search Console filters, comparisons and metric choices, no manual setup required.
- [Bot traffic passes human traffic on Cloudflare's network](https://seomadman.com/news/bot-traffic-passes-human-traffic.md): Cloudflare's CEO says automated requests for HTML pages now outnumber human ones, 18 months ahead of his own forecast.
- [llms.txt and robots.txt have two separate, unrelated standards tracks](https://seomadman.com/news/w3c-llms-txt-standardization-draft.md): A W3C tracking issue on llms.txt and an unrelated IETF working group on robots.txt-adjacent AI signals are getting blended into one false headline.
- [Google removes FAQ rich results from Search](https://seomadman.com/news/faq-rich-results-removed.md): FAQPage markup no longer earns an expanded snippet in Google Search as of 7 May 2026, though the schema stays valid and other crawlers still read it.
- [Publishers with OpenAI deals get 48% more ChatGPT citations](https://seomadman.com/news/openai-licensing-deals-citation-premium.md): A study joining licensing-deal records to 129.3 million AI citations finds a ChatGPT premium for OpenAI partners, but no matching edge on Google.
- [IETF's AI Preferences group is still drafting, not shipping](https://seomadman.com/news/ietf-aipref-robots-txt-successor.md): The IETF's AI Preferences group is standardizing AI training and search signals that extend robots.txt. Still an Internet-Draft, not a shipped standard.
- [IndexNow adoption grows in 2026, but not at Google](https://seomadman.com/news/indexnow-adoption-google-holdout.md): Bing's own published numbers show IndexNow submissions climbing steadily since 2022, yet Google still has no roadmap to join the instant-indexing protocol.
- [What Google and Bing actually say about schema and AI](https://seomadman.com/news/structured-data-ai-citation-priority.md): Schema.org's own numbers, Google's AI documentation and Bing's public statements, separated from unverified SEO claims.
- [Gemini 3.7 Flash reaches AI Mode, a day after its release](https://seomadman.com/news/gemini-3-7-flash-ai-mode.md): Google added Gemini 3.7 Flash to AI Mode's model picker on 14 August 2026, limited to AI Pro and Ultra subscribers, one day after the model shipped.
- [Search Console adds a branded vs non-branded query filter](https://seomadman.com/news/search-console-branded-query-filter.md): A new Performance report filter splits branded and non-branded queries using an AI-assisted classifier, not manual keyword rules.
- [Search Central Live expands to Bogota and Ciudad de Mexico](https://seomadman.com/news/search-central-live-events-latam-europe.md): Google's Search Central team adds Bogota to its live event roster and returns to Ciudad de Mexico in October, alongside a three-day Deep Dive in Barcelona.
- [The May 2026 core update finished after 11 days, its second this year](https://seomadman.com/news/may-2026-broad-core-update-complete.md): Google's May 2026 broad core update ran 21 May to 2 June, its second confirmed core update of 2026. What the dates mean for reading your own traffic.
- [Merchant Center adds AI Performance Insights for share of voice](https://seomadman.com/news/merchant-center-ai-performance-insights.md): A new Merchant Center report benchmarks brand visibility on AI Mode, AI Overviews and Gemini, plus shopping funnel and attribute-gap data.
- [Google's 2026 Merchant Center product spec, three effective dates](https://seomadman.com/news/merchant-center-product-data-spec-2026.md): New shipping and video attributes, a higher minimum image resolution and a longer rollout: what changes on 14 April 2026, 30 June 2026 and 31 January 2027.
- [AI Overview citations are decoupling from search rank](https://seomadman.com/news/ai-overview-citation-rank-decoupling.md): Ahrefs data shows top-10 pages went from 76% to 38% of AI Overview citations in eight months. Ranking well no longer guarantees a citation.
- [Google ships its first Discover-only algorithm update](https://seomadman.com/news/discover-first-dedicated-algorithm-update.md): Google's first Discover-only core update ran three weeks, targeted clickbait and thin republishing. Discover clicks arrive fast: over 70% land on day one.
- [AI Mode passed 200 countries and territories, and entered the EU](https://seomadman.com/news/ai-mode-expands-40-new-areas.md): Google added more than 35 languages and 40 countries to AI Mode, including its first EU markets: Germany, Italy, Spain and Poland.

## Reports

- [Canonical tag adoption, 2025: 68% of desktop pages set one](https://seomadman.com/reports/canonical-tag-adoption-web-almanac-2025.md): The 2025 Web Almanac SEO chapter puts rel=canonical on 68% of desktop and 67% of mobile pages, up from 65%, with mismatches under 1%.
- [AI training now drives 52% of crawler requests, Cloudflare says](https://seomadman.com/reports/cloudflare-ai-training-crawler-share-2026.md): Cloudflare reports AI training made up 52% of identified crawler requests in June 2026, up from 22% in Spring 2025, with search crawling shrinking.
- [Where desktop Google searches end: Datos Q4 2025 data](https://seomadman.com/reports/desktop-search-click-distribution-datos-q4-2025.md): Datos and SparkToro's Q4 2025 clickstream shows 24.5% of US desktop Google searches ended with no click in December, versus 25.1% a year earlier.
- [INP in 2025: 77% of mobile sites pass, but the top 1,000 lag at 63%](https://seomadman.com/reports/inp-good-scores-by-site-rank-2025.md): The 2025 Web Almanac's INP data: 77% of mobile sites have good INP, popular sites trail at 63%, and mobile home pages beat inner pages 80% to 69%.
- [llms.txt fetch counts: what AI crawlers requested on 83 sites](https://seomadman.com/reports/llms-txt-fetch-counts-by-ai-crawler.md): EZY Research's 12-week server-log panel shows OpenAI and Anthropic crawlers fetching llms.txt in single digits while pulling robots.txt thousands of times.
- [How much AI Overview citations overlap with the top 10](https://seomadman.com/reports/ai-overview-citation-source-overlap.md): BrightEdge's own year-long tracking: only 17% of AI Overview citations also rank in the organic top 10, flat since last year, with wide swings by industry.
- [AI referral traffic to publishers doubled in a year, Similarweb finds](https://seomadman.com/reports/ai-referral-traffic-by-industry-2026.md): Similarweb measured 770.7 million monthly AI referral visits worldwide, up 117.4% year over year, led by marketplaces and news.
- [Core Web Vitals by CMS, 2025: Duda and Wix lead, WordPress lags](https://seomadman.com/reports/core-web-vitals-by-cms-platform-2025.md): The 2025 Web Almanac's CMS chapter breaks Core Web Vitals pass rates down by platform: Duda at 85%, Wix up 14 points to 74%, WordPress flat at 45%.
- [WebSite leads schema.org type adoption at 12.73% of mobile pages](https://seomadman.com/reports/schema-org-type-adoption-web-almanac-2024.md): The 2024 Web Almanac breaks JSON-LD down by schema.org type: WebSite tops out at 12.73% of mobile pages, Organization at 7.16%, Product at just 0.77%.
- [Google SERP volatility by category, mid-September 2026](https://seomadman.com/reports/serp-volatility-by-category-september-2026.md): Semrush Sensor's live index reads 2.1 out of 10 for mid-September 2026, but News and Finance run far hotter than Science or Health.
- [Every confirmed Google ranking update since December 2025](https://seomadman.com/reports/google-ranking-updates-2026.md): Eight confirmed updates, with Google's own start dates and rollout durations, and what the pattern says about when to judge a decline in your data.
- [Why four 2026 'ChatGPT market share' numbers do not agree](https://seomadman.com/reports/ai-chatbot-market-share-trackers-compared.md): StatCounter, Similarweb, Sensor Tower and OpenAI itself all published a 2026 ChatGPT usage figure. None of the four is measuring the same thing.
- [How three CTR trackers reported three different position-1 rates](https://seomadman.com/reports/organic-ctr-by-position-2026.md): Three trackers measured 2026 organic CTR by position and reported position 1 anywhere from 27.6% to 39.8%, because none used the same method.
- [How five llms.txt trackers reported five different adoption rates](https://seomadman.com/reports/llms-txt-adoption-tracker-comparison.md): Five independent trackers measured llms.txt adoption in 2026 and reported numbers from 7.4% to 28%, because none counted the same thing.
- [How many confirmed Google updates ship a year, 2015 to 2026](https://seomadman.com/reports/confirmed-update-frequency-2015-2026.md): 87 confirmed major Google updates since 2015, counted year by year, next to Google's own figure for total changes, and why the two must stay separate.
- [Mobile-first indexing, from 2016 test to 2023 completion](https://seomadman.com/reports/mobile-first-indexing-completion-status.md): Tracing Google's mobile-first indexing announcements from 2016 to the 2023 completion notice, and its documentation on mobile-desktop content parity.
- [How often AI Overviews actually appear, January 2025 to April 2026](https://seomadman.com/reports/ai-overviews-serp-prevalence-2026.md): Semrush's own tracking: 6.49% of keywords in January 2025, a July peak near 24.61%, then 15.69% in November - the real trend, not a snapshot.
- [How Google's scaled-content spam enforcement moved through 2026](https://seomadman.com/reports/spam-policy-enforcement-2026.md): From the May 2026 spam-policy rewrite to the August spam update, tracing enforcement against mass-produced, low-value content across 2026.
- [What Google's own Discover documentation actually requires](https://seomadman.com/reports/discover-technical-eligibility-requirements.md): Google's Discover eligibility page sets an exact image-size floor and a named list of content policies. Here is what it says, word for word.
- [What Google has actually said about Google Lens search volume](https://seomadman.com/reports/google-lens-visual-search-growth.md): Google's own dated numbers: 12 billion Lens searches a month in June 2023, nearly 20 billion by October 2024 - and why the 22%/26% claims don't check out.
- [How much link equity does a 301 redirect actually pass?](https://seomadman.com/reports/redirect-link-equity-retention-estimates.md): Google has never published a percentage for how much link equity a 301 redirect passes. The 90-99% figure in circulation comes from somewhere else.
- [How often Google rewrites a meta description: three studies compared](https://seomadman.com/reports/meta-description-rewrite-rate-compared.md): Portent, Ahrefs and Search Engine Journal each measured how often Google rewrites a meta description in 2020: 71%, 62.78% and over 70%, weeks apart.
- [AI crawler block rate: how often a 403 actually stops the bot](https://seomadman.com/reports/ai-crawler-blocking-rate-trend-2026.md): Live HTTP data from Cloudflare's network shows AI crawler 403 rates rising through 2026, distinct from counting robots.txt disallow rules.
- [AI citation rate by content format: what checks out](https://seomadman.com/reports/ai-citation-rate-by-content-format.md): Five precise stats on AI citation rates by content format circulate online. Two trace to real studies. Three do not survive verification.
- [The page experience update: the real 2021-2022 rollout timeline](https://seomadman.com/reports/page-experience-update-timeline.md): Google's own dated posts trace the page experience rollout from 2020 to its 2022 desktop finish, and what the 2026 docs now drop.
- [AI Overview traffic decline: seven claims, four hold up](https://seomadman.com/reports/ai-overview-traffic-decline-estimates-compared.md): Studies put the AI Overview traffic hit from 24% to 80%. We traced seven quoted figures to source; four hold up, and they measure different things.
- [AMP's traffic record: five publishers, five different outcomes](https://seomadman.com/reports/amp-traffic-impact-cases-compared.md): Independent.ie gained 55% mobile traffic on AMP. Kinsta lost 59% of its leads. Here is what really happened across five documented, named case studies.
- [Schema.org's vocabulary hit 823 types with version 30.0 in 2026](https://seomadman.com/reports/schema-org-vocabulary-growth-2026.md): Schema.org's own release notes put the vocabulary at 823 types and 1,529 properties as of version 30.0, alongside a new Google-backed usage dataset.
- [Google's review-fraud scale, and its April 2026 policy tightening](https://seomadman.com/reports/google-review-fraud-enforcement-scale.md): Google's own Maps blog states 2025 review-fraud enforcement scale, and its April 2026 update bans staff review quotas and naming employees in reviews.
- [Penske Media v. Google: the antitrust timeline so far](https://seomadman.com/reports/penske-media-google-antitrust-timeline.md): Penske Media sued Google over AI Overviews in 2025. The dated record: the complaint, Google's dismissal motion, Penske's opposition, and an EU complaint.

## Research

- [What correlates with AI brand mentions? Ahrefs' 75,000-brand study](https://seomadman.com/research/ai-brand-visibility-factors-ahrefs-75k-brands.md): Ahrefs correlated 12 metrics with brand mentions in ChatGPT, AI Mode and AI Overviews: web mentions beat backlinks, and it warns of no causation.
- [How accurate are sitemap lastmod values? Bing's study](https://seomadman.com/research/bing-sitemap-lastmod-accuracy-study.md): Bing's own study of sitemaps found 18% of lastmod values set incorrectly, usually to the generation date, and Google says it only trusts accurate ones.
- [Do AI assistants cite fresher content than Google? Ahrefs data](https://seomadman.com/research/content-freshness-ai-citations-ahrefs-study.md): Ahrefs compared the age of 16.975 million URLs cited by AI assistants against organic Google results. Here is the method, the numbers and the limits.
- [Reddit's top-3 share after the May 2026 core update](https://seomadman.com/research/reddit-top-3-share-se-ranking-core-update-study.md): SE Ranking tracked 100,000 keywords in 20 niches and measured Reddit's share of Google's top three results. This piece reviews its method and limits.
- [Sistrix CTR study: how SERP layout changes position-1 clicks](https://seomadman.com/research/sistrix-ctr-serp-layout-study.md): Sistrix analyzed 80 million keywords and found position 1 averages 28.5% CTR, ranging from 13.7% to 46.9% depending on the SERP layout.
- [A randomized field experiment on AI Overviews and organic clicks](https://seomadman.com/research/ai-overview-ctr-field-experiment.md): A randomized Chrome-extension experiment hid AI Overviews for 1,065 searchers. This piece analyzes Agarwal and Sen's SSRN study of the CTR impact.
- [What happened when someone actually A/B tested author bylines](https://seomadman.com/research/author-byline-eeat-searchpilot-ab-test.md): SearchPilot ran a real controlled SEO split test on author bylines and bios. Result: no detectable ranking gain, and possibly a small loss.
- [SearchPilot test: canonical alone matched a redirect for duplicates](https://seomadman.com/research/canonical-vs-redirect-duplicate-signal-searchpilot-test.md): A SearchPilot split test added 301 redirects atop an existing canonical tag for trailing-slash duplicates. The result stayed inconclusive.
- [What a 10M-page site shows about links and crawl budget](https://seomadman.com/research/internal-linking-crawl-budget-botify-case-study.md): Botify's case study of a US auto marketplace ties internal-link depth to crawl activity: a 19x increase in crawling once linking was fixed.
- [Why title rewrite rate studies disagree: 33% vs 61% vs 76%](https://seomadman.com/research/title-tag-rewrite-definitions-compared.md): Ahrefs found a 33.4% title rewrite rate, far below Zyppy's 61.6% and Search Engine Land's 76%. The gap traces to how each study defines a match.
- [Who blocks AI crawlers: 60 robots.txt files, read in full](https://seomadman.com/research/ai-crawler-policies-news-sites.md): We read the robots.txt of 60 publishers and SEO vendors. News sites block AI crawlers almost universally. The SEO industry does not.
- [Do internal links still track with Google Search traffic in 2026?](https://seomadman.com/research/internal-linking-crawl-depth-zyppy-study.md): Zyppy's 23-million-link study and Google's own crawling documentation show why pages with few internal links struggle to get discovered and clicked.
- [Review and AggregateRating schema: Google's real required fields](https://seomadman.com/research/review-aggregaterating-schema-requirements.md): Google's own review-snippet documentation names exact required properties and exact abuse rules. Most markup fails one of those, not from being absent.
- [Pagination and infinite scroll: what Google actually indexes in 2026](https://seomadman.com/research/pagination-infinite-scroll-indexing.md): rel=next/prev has been dead as an indexing signal since 2019, per Google's own words. Infinite scroll without real URLs is the same mistake in new clothes.
- [Do backlinks still correlate with rankings in 2026?](https://seomadman.com/research/backlinks-ranking-correlation-2026.md): Backlinko's 11.8M-result study and Ahrefs' 1M-keyword study both find a positive link between referring domains and rank, but the coefficient is weak.
- [Hreflang error rates: what's actually sourced, and what isn't](https://seomadman.com/research/hreflang-error-prevalence-2026.md): Two widely repeated hreflang error statistics do not trace to any real source. Here is what could be verified instead, from Google's own documentation.
- [AI citation hallucination rates: what three real studies found](https://seomadman.com/research/ai-citation-hallucination-rates.md): GPTZero, the Tow Center and a Cureus study each measured AI citation hallucination differently, and none of their numbers agree with each other.
- [What academic research actually says about AI citation factors](https://seomadman.com/research/geo-citation-factors-academic-studies.md): Four 2026 papers measured what predicts citation by AI search engines. Position and relevance win; most citations skip brand domains entirely.
- [Noindex does not save crawl budget, per Google's own documentation](https://seomadman.com/research/noindex-crawl-budget-reality.md): A common crawl-budget fix is backwards. Google's own documentation says noindex still costs a full request before the page gets dropped from the index.
- [Site reputation abuse: what the evidence actually shows](https://seomadman.com/research/site-reputation-abuse-what-is-actually-measured.md): Google's manual actions against parasite SEO are 18 months old. Here is what is documented versus what is anecdotal case tracking.
- [NavBoost: what the DOJ trial and the API leak actually confirmed](https://seomadman.com/research/navboost-doj-trial-click-signals.md): Court testimony and a leaked Google document, read together, describe a click-based re-ranking system Google spent years declining to confirm in public.
- [VideoObject schema: the required properties Google actually documents](https://seomadman.com/research/videoobject-schema-required-properties.md): Google documents three required VideoObject properties, not the four often claimed, plus exact date and duration formats and a rich-result caveat.
- [Core Web Vitals and rankings: what the correlation shows](https://seomadman.com/research/core-web-vitals-ranking-correlation-2026.md): CrUX data and a 20,000-URL ranking study both show a link between Core Web Vitals and rank, but Google's own docs put content relevance first.
- [Googlebot's two-wave rendering: how long JS content actually waits](https://seomadman.com/research/javascript-rendering-googlebot-delay.md): A 2024 Vercel and MERJ study measured the real gap between crawl and render at scale. The median was seconds; the tail stretched to a full day.
- [E-E-A-T and author schema: what is actually verifiable](https://seomadman.com/research/author-schema-eeat-what-is-verifiable.md): SEO content repeats precise E-E-A-T ranking-weight percentages. We checked the two most-cited figures against their sources and Google's own documentation.
- [Does content length correlate with rankings and AI citations?](https://seomadman.com/research/content-length-ranking-citation-correlation.md): Ahrefs' December 2025 study puts the word count to AI Overview citation correlation at 0.04. Backlinko's 11.8M-result study finds no ranking edge either.
- [What Google actually names in its own ranking systems guide](https://seomadman.com/research/google-ranking-systems-documented.md): Google publishes a real, maintained list of the named systems behind Search ranking. Read directly, not summarized secondhand.
- [Local ranking factor percentages: what's real, what's not](https://seomadman.com/research/local-seo-ranking-factors-verifiable.md): A specific local ranking percentage breakdown circulates widely. It doesn't match Whitespark's real 2026 chart, and Google names no percentages at all.
- [x-default's real history: what Google has actually said, on record](https://seomadman.com/research/hreflang-x-default-google-statements.md): x-default has been explained by Google at least three times since 2013. Here is the real, dated wording each time, and what current documentation says.
- [HTTPS as a Google ranking signal in 2026](https://seomadman.com/research/https-ranking-signal-2026.md): Google called HTTPS a very lightweight ranking signal in 2014 and has never revised that number. Adoption data now shows why it barely needs to.
- [Featured snippet stats: which numbers are real, and which aren't](https://seomadman.com/research/featured-snippets-what-is-verifiable.md): Featured snippet prevalence and CTR figures vary by nearly 2x across sources. Here is which trace to a real, dated study, and which don't trace anywhere.
- [Article schema has no required properties, only recommended ones](https://seomadman.com/research/article-schema-no-required-properties.md): Google's own Article structured data documentation names zero required properties, only recommended ones, which changes how schema work gets prioritized.

## Studies

- [Merchant Center feed fixes and three click gains, per Uproer](https://seomadman.com/studies/google-merchant-center-feed-optimization-uproer.md): Uproer's published case study reports feed-level Google Merchant Center changes lifted clicks 130%, 116% and 3,500 for three unnamed ecommerce brands.
- [JunkCarsUs: HCU recovery from 30-50 to 400-500 clicks a day](https://seomadman.com/studies/hcu-recovery-junkcarsus-seoprofy-case.md): SeoProfy's case study on JunkCarsUs: after the September 2023 HCU, pruning pages and rewriting templates preceded a rise to 400-500 daily clicks.
- [Log analysis cut a jewelry site from 16M to 730K crawlable pages](https://seomadman.com/studies/jetoctopus-log-analysis-parameter-crawl-waste-case-study.md): A JetOctopus case study: log files showed Googlebot spending crawl on filter, sort and pagination URLs, and closing them shrank the site to 730K pages.
- [Nuvemshop lifted good LCP from 57% to 96% by fixing image loading](https://seomadman.com/studies/nuvemshop-lcp-image-priority-case-study.md): Nuvemshop's web.dev case study: removing lazy loading on top images and adding fetchpriority took good LCP from 57% to 96% across its stores.
- [Programmatic SEO case: 100 pages, 398% traffic, per Suso Digital](https://seomadman.com/studies/programmatic-seo-saas-100-pages-suso-digital.md): Suso Digital reports a software supply chain client grew organic traffic 398.49% in 18 months from about 100 template pages. What the case shows.
- [CoinStats fixed a Core Web Vitals bug, tripled search impressions](https://seomadman.com/studies/coinstats-core-web-vitals-organic-traffic.md): DebugBear's case study: CoinStats found Base64 images were bloating 15,000 pages, fixed it, and saw Good URLs and search impressions both increase 3x.
- [Home Science Tools: pruning 200 blog pages, organic sessions up 104%](https://seomadman.com/studies/homescience-tools-content-pruning-case-study.md): Inflow's case study on HomeScienceTools.com: removing roughly 200 low-value blog pages preceded a 104% rise in sessions and 102% rise in transactions.
- [IFTTT's internal linking fix and its 33% YoY traffic gain](https://seomadman.com/studies/ifttt-internal-linking-traffic-case-uproer.md): Uproer's case study on IFTTT: searchbots reached only 59 pages via internal links until a fix, after which the site saw 33% YoY organic traffic growth.
- [Marshfield Clinic: 454% CTR gain from schema markup](https://seomadman.com/studies/marshfield-clinic-schema-markup-ctr-case-study.md): Schema App's customer story on Marshfield Clinic reports a 454% CTR increase when a Review Snippet was awarded, plus 32% from entity linking.
- [Simms Fishing's Magento to Shopify migration: the real numbers](https://seomadman.com/studies/simms-fishing-magento-shopify-migration.md): Inflow's case study: Simms Fishing saw organic traffic up 126% YoY and non-brand category traffic up 5,642% after a Magento to Shopify move.
- [llms.txt is a vendor standard, not a publisher one](https://seomadman.com/studies/llms-txt-adoption-2026.md): Only 14 of 60 major sites serve an llms.txt. Half of them sell SEO or hosting software. One is a news publisher. The file has an audience problem.
- [How often Google rewrites a title tag: 61.6% to 76%](https://seomadman.com/studies/title-tag-rewrite-rate-study.md): Two independent studies measured how often Google rewrites a title tag rather than using it as written: 61.6% in 2022, 76% by 2025.
- [SearchPilot: removing a breadcrumb link cut organic traffic 5.5%](https://seomadman.com/studies/breadcrumb-link-removal-ab-test-searchpilot.md): SearchPilot split-tested removing a self-referential breadcrumb link on PLPs. Traffic fell 5.5%, likely from a schema markup mismatch left behind.
- [Does llms.txt do anything? Three studies say mostly no](https://seomadman.com/studies/llms-txt-measured-traffic-impact.md): 97% of published llms.txt files get zero AI-bot requests. A 10-site traffic test found no effect in 8 cases. The one positive figure has its own confound.
- [SearchPilot: canonicalizing to a variant lifted variant traffic 22%](https://seomadman.com/studies/canonical-product-variant-ab-test-searchpilot.md): SearchPilot canonicalized product pages to a variant's URL instead of self-referencing. Variant pages gained 22%; main pages stayed inconclusive.
- [DOM.RIA's internal linking rebuild and its Googlebot crawl visits](https://seomadman.com/studies/internal-linking-crawl-coverage-case.md): JetOctopus's case study on real estate site DOM.RIA, reworking internal links to poorly-crawled directory pages roughly tripled Googlebot visits to them.
- [AI citation patterns shift sharply by search intent, Wix data shows](https://seomadman.com/studies/ai-citation-by-search-intent-wix.md): Wix Studio's AI Search Lab found articles win informational queries 2.7x more, and listicles and product pages win commercial and transactional ones.
- [Three named companies that disclosed real AI-search traffic losses](https://seomadman.com/studies/named-publisher-traffic-declines.md): Chegg, Business Insider and HubSpot all show real, checkable declines. A widely repeated CNN figure does not survive a source check.
- [How long domain migrations take to recover organic traffic](https://seomadman.com/studies/domain-migration-recovery-time.md): A 892-migration study found the average new domain took 523 days to match the old domain's organic traffic, and 17% never did within 1,000 days.
- [Google's own data: Rakuten and Vodafone Core Web Vitals A/B tests](https://seomadman.com/studies/rakuten-vodafone-core-web-vitals-case-studies.md): Google's web.dev logged two named A/B tests: Rakuten 24 saw 53.37% more revenue per visitor, Vodafone Italy saw 8% more sales after a 31% LCP gain.
- [SearchPilot: promoting an H2 to H1 lifted organic traffic 4.5%](https://seomadman.com/studies/h2-to-h1-ab-test-searchpilot.md): SearchPilot split-tested changing a travel site's top heading from an H2 to an H1. The change produced a statistically significant 4.5% traffic increase.
- [JSON-LD structured data adoption grew from 34% to 41% of pages](https://seomadman.com/studies/structured-data-adoption-web-almanac.md): HTTP Archive's Web Almanac found JSON-LD on 41% of pages in 2024, up from 34% in 2022, while RDFa and Open Graph stayed the most common formats.
- [One publisher's Google Discover traffic loss and recovery](https://seomadman.com/studies/discover-traffic-recovery-case.md): A consultant's self-reported case: a client site's Discover impressions hit zero for weeks, then recovered after a quality fix. One case, not a study.
- [Deloitte: 0.1s faster mobile speed lifted retail conversion 8.4%](https://seomadman.com/studies/page-speed-conversion-rate-impact.md): Deloitte's 2019 study of 37 brand sites found a 0.1s mobile speed gain lifted retail conversion 8.4%. Shopify data adds a 100ms benchmark.
- [Ahrefs: AI Overviews cut position-1 CTR by 58%](https://seomadman.com/studies/ai-overviews-click-through-rate-decline.md): Ahrefs analyzed 300,000 keywords via Google Search Console and found AI Overviews now cut position-1 organic CTR by 58%, up from 34.5% a year earlier.
- [SearchPilot: FAQ content lifted traffic, FAQ schema did not](https://seomadman.com/studies/faq-content-ab-test-searchpilot.md): SearchPilot split-tested FAQ content and FAQ schema. Content added 9.7% more organic clicks; removing schema alone changed nothing.
- [Zero-click Google searches hit 68% in the US](https://seomadman.com/studies/zero-click-search-2026.md): SparkToro and Similarweb's June 2026 report puts US Google zero-click search at 68.01%, up from 60.45% in 2024.
- [Mobile vs desktop Core Web Vitals: INP gap widest, CLS flips](https://seomadman.com/studies/mobile-desktop-cwv-pass-rate-gap.md): HTTP Archive's July 2025 data broken down by metric: INP splits mobile and desktop by 20 points, LCP by 12, and CLS reverses the pattern entirely.
- [SearchPilot: nearby-region links lifted organic traffic 7%](https://seomadman.com/studies/nearby-regions-internal-linking-ab-test-searchpilot.md): SearchPilot split-tested linking each of 8,000 regional pages to its 6 nearest neighbors. Linked pages saw a 7% organic traffic uplift over controls.
- [Google's own numbers: structured data lifted CTR 25-82%](https://seomadman.com/studies/structured-data-ctr-google-case-studies.md): Google's own documentation reports Rotten Tomatoes at 25% higher CTR and Nestle at 82% higher CTR from structured data. Here is what each figure measures.

## Tools

- [Hreflang XML sitemap generator](https://seomadman.com/tools/hreflang-sitemap-xml-generator.md): Build a sitemap with xhtml:link hreflang annotations for localized pages, with every alternate listed on every URL as Google's documentation requires.
- [HTTP status code crawl handling checker](https://seomadman.com/tools/http-status-code-crawl-handling-checker.md): Paste status codes and see how Google's crawlers document handling each one, plus a redirect hop count against Google's 10-hop default.
- [Link rel attribute auditor: sponsored, ugc, nofollow](https://seomadman.com/tools/link-rel-attribute-auditor.md): Audit the links in pasted HTML against Google's rel qualifiers: sponsored for paid links, ugc for user content and nofollow when neither applies.
- [Robots meta tag and X-Robots-Tag validator](https://seomadman.com/tools/robots-directive-validator.md): Validate robots meta tags and X-Robots-Tag headers against the rules Google documents, and see the combined result for Googlebot.
- [URL normalizer and duplicate variant finder](https://seomadman.com/tools/url-normalizer-duplicate-variant-finder.md): Normalize a list of URLs by RFC 3986 rules and your own policy, then see which URLs collapse into the same page and need one canonical.
- [Faceted navigation parameter analyzer](https://seomadman.com/tools/faceted-navigation-parameter-analyzer.md): Check a filtered listing URL's query parameters against Google's own documented faceted navigation guidance, and get a suggested robots.txt block.
- [International targeting strategy planner](https://seomadman.com/tools/international-targeting-strategy-planner.md): Score a ccTLD, subdomain, subdirectory or URL-parameter structure against Google's own documented geotargeting pros and cons for your constraints.
- [Meta refresh vs. 301 redirect checker](https://seomadman.com/tools/meta-refresh-vs-redirect-checker.md): Parse a meta refresh tag's delay and target, and see which redirect signal Google actually reads from it: permanent at 0 seconds, temporary above 0.
- [Pagination and canonical conflict checker](https://seomadman.com/tools/pagination-canonical-conflict-checker.md): Check a paginated sequence's URLs and canonicals against Google's guidance, and catch the common mistake: consolidating every page to page 1.
- [Robots.txt syntax validator](https://seomadman.com/tools/robots-txt-syntax-validator.md): Lint a whole robots.txt file for structural and syntax errors against RFC 9309 and Google's own interpretation of it, line by line.
- [JSON-LD syntax and required-field validator](https://seomadman.com/tools/json-ld-validator.md): Paste a JSON-LD block and get real syntax errors with line numbers, plus a check against the properties Google actually requires for that schema type.
- [Redirect chain analyzer: check hop count, loops and mixed codes](https://seomadman.com/tools/redirect-chain-analyzer.md): Paste a redirect chain you collected yourself and check it against Google's guidance on chain length, loops, mixed 301/302 codes and protocol drift.
- [AI answer readiness checker for articles](https://seomadman.com/tools/ai-answer-readiness-checker.md): Score an article on the structural properties that decide whether an answer engine can extract, quote and attribute it.
- [Image alt text auditor](https://seomadman.com/tools/image-alt-text-auditor.md): Paste HTML and check every image's alt attribute for missing, empty, generic and keyword-stuffed alt text against Google's own guidance.
- [robots.txt and llms.txt generator with an AI policy](https://seomadman.com/tools/robots-and-llms-txt-generator.md): Decide which AI crawlers may take your content, see what each one actually does, and generate both files from that one decision.
- [Structured data generator for search and AI](https://seomadman.com/tools/schema-markup-generator.md): Build valid JSON-LD for Article, NewsArticle, FAQPage, VideoObject, Organization and BreadcrumbList, with every required property checked.
- [SERP snippet preview with pixel-accurate truncation](https://seomadman.com/tools/serp-snippet-preview.md): Preview a title and meta description as Google renders them, measured in pixels rather than characters, on desktop and mobile.
- [Breadcrumb schema generator](https://seomadman.com/tools/breadcrumb-schema-generator.md): Build a valid BreadcrumbList JSON-LD trail from a repeatable list of page names and URLs, checked against Google's own documented structure.
- [Site migration redirect map builder](https://seomadman.com/tools/redirect-map-builder.md): Build a 1:1 old URL to new URL redirect map for a site migration and export it as CSV, Apache .htaccess or Nginx rewrite rules.
- [Core Web Vitals thresholds checker](https://seomadman.com/tools/core-web-vitals-checker.md): Classify an LCP, INP and CLS number against Google's published Good, Needs Improvement and Poor thresholds, and see the overall pass or fail.
- [Canonical tag checker](https://seomadman.com/tools/canonical-tag-checker.md): Check a declared canonical URL against Google's documented rules: absolute URL, HTTPS, self versus cross-domain, and tracking parameters.
- [robots.txt tester: check a user-agent against a path](https://seomadman.com/tools/robots-txt-tester.md): Paste a robots.txt, pick a crawler and a URL path, and see the exact Allow or Disallow line that decides the outcome.
- [Sitemap vs robots.txt conflict checker](https://seomadman.com/tools/sitemap-robots-conflict-checker.md): Paste a sitemap and a robots.txt, then see every URL the sitemap lists for crawling that robots.txt also blocks for the tested user-agent.
- [Readability and reading time calculator](https://seomadman.com/tools/readability-reading-time-calculator.md): Score pasted text with the Flesch reading ease formula and estimate reading time, computed live in your browser from real, cited constants.
- [Keyword cannibalization checker](https://seomadman.com/tools/keyword-cannibalization-checker.md): Compare titles or H1s across your own pages and flag near-duplicate pairs using Jaccard word-overlap similarity, entirely in your browser.
- [Bulk title and meta description length checker](https://seomadman.com/tools/bulk-title-meta-checker.md): Paste many pages at once and see which titles and descriptions will truncate in Google search results, measured in pixels.
- [Hreflang tag generator and validator](https://seomadman.com/tools/hreflang-tag-generator.md): Build correct <link rel="alternate" hreflang> tags for a set of localized URLs and check them against Google's reciprocity and x-default rules.
- [Open Graph and X card preview](https://seomadman.com/tools/social-card-preview.md): Preview how a title, description and image will render as a Facebook or LinkedIn link card and as an X summary_large_image card.
- [URL structure analyzer](https://seomadman.com/tools/url-structure-analyzer.md): Check a URL's length, path depth, parameters and separators against Google's documented URL structure guidance and labelled heuristics.
- [XML sitemap structure validator](https://seomadman.com/tools/xml-sitemap-validator.md): Paste raw sitemap XML for real parse errors, a namespace and structure check, and the 50,000 URL and 50MB limits from the sitemaps.org protocol.
- [Meta robots tag builder](https://seomadman.com/tools/meta-robots-tag-builder.md): Build a syntactically correct robots meta tag or X-Robots-Tag header, with Google-specific directives flagged and contradictions caught.
- [Google search operator query builder](https://seomadman.com/tools/search-operator-builder.md): Build a Google search query from site:, filetype:, exact phrase, exclude and OR fields, with operators Google no longer documents clearly flagged.
- [Anchor text diversity calculator](https://seomadman.com/tools/anchor-text-diversity-calculator.md): Classify inbound anchor texts against a target keyword and see the real split between exact match, partial match, branded, generic and naked URL anchors.
- [Keyword density and content length checker](https://seomadman.com/tools/keyword-density-checker.md): Count words and keyword occurrences in your draft and see the density as a diagnostic number, not an optimal-percentage target that does not exist.

## Topics

- [Core updates](https://seomadman.com/topics/core-updates): Coverage of Google core algorithm updates, what each rollout changed, and how to read the movement in your own data.
- [AI search](https://seomadman.com/topics/ai-search): How AI Overviews, ChatGPT, Perplexity and Claude select and cite sources, and what that changes about SEO.
- [Technical SEO](https://seomadman.com/topics/technical-seo): Crawl budget, rendering, status codes, canonicals and the infrastructure decisions that decide whether pages get indexed.
- [Structured data](https://seomadman.com/topics/structured-data): Schema.org markup that earns rich results and gives answer engines an unambiguous machine reading of a page.
- [Search Console](https://seomadman.com/topics/search-console): Getting real answers out of Search Console: query data, index coverage, sampling limits and the traps in the reports.
- [Indexing](https://seomadman.com/topics/indexing): Discovery, crawl scheduling, index selection and the reasons Google keeps pages out of the index.
- [Content strategy](https://seomadman.com/topics/content-strategy): Topical authority, intent coverage and editorial standards that hold up across core updates and AI answers.

## Optional

- [Full corpus](https://seomadman.com/llms-full.txt)
- [JSON Feed](https://seomadman.com/feed.json)