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Free AI SEO Checker: How to Rank in ChatGPT, Perplexity and AI Overviews

A developer built a free AI SEO checker that audits any public URL in seconds for signals AI answer engines like ChatGPT search, Perplexity and Google AI Overviews rely on, returning a score out of 100 with fixes for each warning. The tool fetches the page along with its robots.txt, llms.txt and sitemap, then runs weighted checks across on-page factors, discovery files and crawler rules for nine named bots. It draws on Google, OpenAI, Perplexity and Anthropic crawler documentation and the KDD 2024 GEO paper, which found citing sources, quotations and statistics produced the largest visibility gains while keyword stuffing did not help.

by read10 min views2 publishedOct 30, 2026

Cross-posted from my blog. The original, with any updates, lives on fabwaseem.com.

An AI SEO checker tests whether AI answer engines such as ChatGPT search, Perplexity and Google AI Overviews can reach, read and quote a page. I built a free one that runs a GEO audit on any public URL in a few seconds and gives you a score out of 100 plus a fix for every warning: open the free AI SEO checker. No account needed.

This guide explains what an AI SEO check covers, what each check means, how the score works, how to run the tool, and what the research and the search engines themselves say about how to rank in ChatGPT and other AI answers.

An AI SEO checker is a tool that audits a web page for the signals AI answer engines rely on: whether AI crawlers are allowed in robots.txt, whether the page has a sitemap, llms.txt, structured data, clean metadata and headings, and whether its opening text answers the topic directly. It reports what passes, what fails and how to fix it.

Definition: AI SEO, also called GEO (generative engine optimization) or AEO (answer engine optimization), is the practice of making content easy for AI systems to find, understand and cite in generated answers. A GEO audit is a checklist review of a page against those requirements.

The term GEO comes from the research paper GEO: Generative Engine Optimization by Aggarwal and colleagues from Princeton and IIT Delhi, published at KDD 2024.

TL;DR

To rank in ChatGPT search, Perplexity and Google AI Overviews, make sure their crawlers can reach the page, that the page is indexed by the underlying search engine, and that it answers the question clearly in the first lines with sourced facts. Add structured data that matches the visible text, keep titles and headings precise, and publish a sitemap.

There is no paid placement or secret switch. What the engines and the research agree on:

Source What it says
Google: AI features and your website No extra requirements for AI Overviews or AI Mode. The page must be indexed and eligible for a snippet. Allow crawling, use internal links, keep important content in text, and make structured data match visible text.
OpenAI crawlers OAI-SearchBot is used for ChatGPT search results; GPTBot is for training; ChatGPT-User fetches pages for user actions. Each respects robots.txt separately.
Perplexity crawlers PerplexityBot indexes pages for Perplexity answers; Perplexity-User fetches on a user's request.
Anthropic crawlers ClaudeBot and related agents follow robots.txt.
GEO paper (KDD 2024) Citing sources, adding quotations and adding statistics gave the largest visibility gains; keyword stuffing did not help.

The practical order is: be crawlable, be indexed, be clear, be citable. The checker covers the first three directly and gives hints for the fourth.

The checker fetches the URL you enter plus its robots.txt, llms.txt and sitemap, then runs a set of checks in three groups: on-page (HTTPS, response time, title, meta description, canonical, Open Graph, headings, answer-first lead), discovery (JSON-LD, llms.txt, sitemap) and AI crawler rules for nine named bots.

Every check, with the weight it carries in the score:

Check Group Weight Passes when
HTTPS Page 8 The final URL after redirects is https
Response time Page 6 HTML arrives in 800 ms or less (warn up to 1,800 ms)
Title Page 8 A title of 15 to 65 characters
Meta description Page 8 A description of 50 to 160 characters
Canonical Page 6 An absolute rel=canonical URL
Open Graph Page 6 og:title, og:description and og:image present
Headings Page 8 One H1, then H2 and H3 in order without skipped levels
Answer-first lead Page 8 The opening paragraph is a short, direct answer (roughly 40 to 320 characters, 70 words or fewer)
JSON-LD Discovery 10 At least one valid JSON-LD block with a schema.org type
llms.txt Discovery 10 /llms.txt exists with an H1 and a summary or links
Sitemap Discovery 8 A sitemap is found from robots.txt or /sitemap.xml
AI crawlers Crawlers 2 each Each bot's robots.txt rule matches the expected access

The crawler rows check these user agents: GPTBot, OAI-SearchBot, ChatGPT-User, ClaudeBot, PerplexityBot, Google-Extended, CCBot and Applebot-Extended (expected: allowed), plus Bytespider (expected: blocked, since it is a high-volume scraper rather than a citation crawler). If you deliberately block training bots such as GPTBot or CCBot, that row will fail; the choice is yours, and the tip explains the trade-off.

The score is a weighted average out of 100. Each check has a weight, and a pass earns its full weight, a warning earns half, and a fail earns nothing. The total earned is divided by the total possible weight and rounded. Discovery checks such as JSON-LD and llms.txt weigh most because they decide whether an engine understands the page at all.

So a page that passes everything except a warning on the answer-first lead loses 4 of 104 possible points and scores around 96. That is what this site scored when I tested the homepage: every check passed except the answer-first lead, which the tool flagged with "The opening text is there, but it is not a short direct answer."

The tool labels the score with a band:

Score Band What to do
85 to 100 Strong Polish warnings, focus on content quality
70 to 84 Good Fix the remaining fails and the heaviest warnings
50 to 69 Mixed Fix every fail, starting with crawler access and discovery
Below 50 Weak Start with crawler access, sitemap and metadata

Open the AI SEO checker, paste a full public URL, and press Check this URL. In a few seconds you get a score, a pass, warn or fail status for each check, a one-line detail of what was found, and a fix with a link to a longer guide. Fix the fails first, redeploy, and run it again.

Step by step:

https://, into the The most common failures are a robots.txt that blocks AI search crawlers, a missing llms.txt, no JSON-LD, a missing or duplicate meta description, and a page that opens with filler instead of an answer. Each has a small, specific fix, and most take minutes in a modern framework such as Next.js.

Failure Why it matters Fix
OAI-SearchBot or PerplexityBot blocked That engine cannot fetch the page to cite it Allow them in robots.txt; named groups do not inherit * rules underRFC 9309 , so repeat your disallows in each group
No llms.txt Agents lack a quick map of your site Create one with the free llms.txt generator
No JSON-LD Engines must guess what the page is Add Article, Organization, Person, Product or FAQPage markup that matches the page ( Google's guide )
Weak or missing meta description Snippets and summaries pull poor text Write 120 to 160 characters that answer the page's main question
Skipped heading levels Structure is harder to parse into sections One H1, then H2s, then H3s
No answer in the first paragraph Engines quote clear, direct statements Open with a 40 to 60 word answer, then the detail
Slow HTML Crawlers may time out or crawl less Cache HTML, cut server work, use a CDN
No sitemap New pages are found more slowly Publish /sitemap.xml and list it in robots.txt (sitemaps.org )

A robots.txt that allows AI search crawlers while keeping private paths closed looks like this:

User-agent: *
Allow: /
Disallow: /admin/

User-agent: OAI-SearchBot
Allow: /
Disallow: /admin/

User-agent: PerplexityBot
Allow: /
Disallow: /admin/

User-agent: Bytespider
Disallow: /

Sitemap: https://example.com/sitemap.xml

For a full Next.js implementation of robots, sitemap, metadata and JSON-LD, see my guide to Next.js SEO for AI search. For social previews, the free OG image generator makes the og:image the checker looks for.

Write each section so it can be lifted out and quoted on its own: a question as the heading, a direct 40 to 60 word answer first, then detail, tables and steps. Cite primary sources, include concrete numbers you can back up, and define terms plainly. The GEO paper found these citation, quotation and statistics changes gave the biggest gains.

From the GEO paper, in its own benchmark:

Method Effect on visibility in generated answers
Cite sources, add quotations, add statistics Largest gains, about 30 to 40% on the position-adjusted word count metric
Fluency and easy-to-understand rewrites About 15 to 30%
Authoritative, persuasive tone No significant improvement
Keyword stuffing Little or no improvement, and worse on Perplexity in their test

The paper also reports that lower-ranked pages gained most: in one test, citing sources raised visibility for pages ranked fifth in search results by 115%. Treat these as research results on a benchmark, not guarantees, but the direction matches what the engines say: clear, sourced, well-structured text wins.

A practical writing checklist:

Mostly no. AI search reuses the foundations of regular SEO: crawlable, indexed, fast pages with accurate metadata and helpful content. The differences are emphasis. AI engines quote passages, so answer-first writing, clear sections, cited facts and structured data matter more, and there are extra crawler user agents to allow in robots.txt.

Area Regular SEO AI SEO / GEO
Goal Rank a blue link Be quoted or cited in an answer
Crawlers Googlebot, Bingbot Plus OAI-SearchBot, PerplexityBot, ClaudeBot and others
Content unit The page The passage or section
Signals Links, relevance, experience The same, plus clarity, citations and direct answers
Extra files robots.txt, sitemap Optionally llms.txt
Measurement Rankings, clicks Citations, referral traffic from AI tools, Search Console "Web" data

Google notes that traffic from AI Overviews and AI Mode is counted in Search Console's Performance report under the Web search type, so you measure it there alongside normal search.

Yes. The AI SEO checker is free with no account and no email gate. A small rate limit (a few runs per visitor every 10 minutes) keeps it fast and stops abuse.

A GEO audit is a review of a page against what generative engines need: crawler access, indexability, metadata, structured data, llms.txt, a sitemap, clear headings and answer-first content. The checker automates the technical part and returns a score with fixes.

No. No tool or agency can guarantee it. Google states that meeting every requirement does not guarantee crawling, indexing or serving. You can remove the technical blockers and make the content easy to cite, which improves your chances.

It depends on your goals. GPTBot collects training data, while OAI-SearchBot powers ChatGPT search results. OpenAI documents them separately, so you can block GPTBot and still allow OAI-SearchBot if you want to appear in ChatGPT search without contributing training data.

In this tool, yes: llms.txt is one of the heaviest checks, at 10 points. In the real world, Google says you do not need it for AI Overviews. It helps agents and assistants that read it, and it costs little to add.

Run it after every deploy that touches templates, robots.txt or metadata, and on each new key page. A robots.txt change can silently block an AI crawler, so a quick re-check after infrastructure changes is worth it.

* rules. Paste your most important page into the free AI SEO checker and fix the first failure it shows. If llms.txt is missing, make one with the llms.txt generator. All my free tools are on the tools page, and my work is on the projects page.

Originally published on fabwaseem.com.

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