Tools to make your website readable by AI crawlers in 2026: five picks from free checks to rendering
Five tools that help ChatGPT, Claude, and Perplexity read your website, and the fixes to make first.
A plain-text version of this site for AI assistants is at https://contengi.com/llms.txt, with the full product documentation in one file at https://contengi.com/llms-full.txt. Every page is also available as markdown by adding .md to its URL.
TL;DR
- The best tools to make your website readable by AI crawlers in 2026 are Contengi's free AI bot view to see what crawlers get, Prerender.io to serve rendered HTML to bots, Cloudflare to control crawler access and serve Markdown, Yoast SEO to generate an llms.txt file, and Screaming Frog to audit rendering across a whole site.
- The AI bot view loads your page as GPTBot with no JavaScript and as a real browser, scores the share of words that made it across, and checks robots.txt for 14 bots, for free.
- Prerender.io starts at $59 a month for 30,000 renders, charged monthly, with a 30-day free trial.
- Yoast SEO generates an llms.txt file in one click, and the feature is free for everyone.
- Fix the HTML your server sends before anything else, because the crawlers behind ChatGPT, Claude, and Perplexity read the raw HTML and skip the JavaScript.
A JavaScript-heavy website can be a shop with the blinds down. Customers who walk in see a lovely display, but anyone peering through the window from the street, which is roughly what an AI crawler does, sees an empty room and walks on.
This list covers five tools that help AI crawlers read your site, from free checks to rendering services. We built Contengi, so it goes first, and each of the others is a strong pick for something we don't do. The rest are in no specific order.
AI crawler readability tools at a glance
| Tool | Best for | Starting price |
|---|---|---|
| Contengi AI bot view | Seeing a page the way AI crawlers see it | Free; the platform is from $50 a month |
| Prerender.io | Serving rendered HTML to crawlers | $59 a month, charged monthly, 30-day free trial |
| Cloudflare | Controlling crawler access and serving Markdown | Free plan; Pro $20 a month billed annually, or $25 monthly |
| Yoast SEO | Generating llms.txt on WordPress or Shopify | Free |
| Screaming Frog SEO Spider | Auditing rendering across a whole site | Free up to 500 URLs; licence £199 a year |
1. Contengi: best for when you want to see what AI crawlers get from your page
Contengi's free AI bot view loads your page twice, once as GPTBot with no JavaScript and once in a real browser, then matches every heading, paragraph, and link a visitor sees against the bot's copy. The score is the share of words that made it across, and the scan lists exactly which blocks went missing.
It also reads your robots.txt the way crawlers do for 14 bots across AI search and AI training, catches firewalls that turn GPTBot away, and checks your title, canonical, schema, llms.txt, and sitemap. Nothing about the scanned page is stored. Inside the platform, LLM tracking then shows whether ChatGPT, Claude, Gemini, Grok, and Perplexity mention you once they can read you. The platform is from $50 a month, plus your own Anthropic key.
What it doesn't do: Contengi doesn't render your JavaScript, change your server, or edit robots.txt for you. It shows the problem and writes content worth citing, and you fix rendering with your developer or a tool below.
Choose it if: you want a free, quick answer to whether ChatGPT can read a page before you spend money fixing it.
2. Prerender.io: best for when your site is a JavaScript app
Prerender.io serves a fully rendered HTML version of your pages to crawlers, including those from Google and ChatGPT, while visitors still get the live app. You control how long the cache lasts, and it revisits your sitemap to keep pages fresh.
Starter costs $59 a month for 30,000 renders, with extra renders at $2.25 per 1,000, and plans are charged monthly. You pay only for cached pages, and there is a 30-day free trial.
Choose it if: your site is a single-page app and a rebuild with server rendering isn't on the cards this year.
3. Cloudflare: best for when you want control over which bots get in
Cloudflare's AI Crawl Control monitors AI crawler activity, lets you allow or block individual crawlers, and shows which ones honour robots.txt, on all plans. Its Markdown for Agents feature converts HTML to Markdown on the fly when a client asks for it, stripping navigation and scripts, and it is available on Pro, Business, and Enterprise at no extra cost.
Cloudflare's free plan costs $0, and Pro is $20 a month billed annually, or $25 billed monthly.
Choose it if: your site already runs through Cloudflare and you want one place to decide which AI bots read it.
4. Yoast SEO: best for when you want an llms.txt file without writing one
Yoast SEO can generate an llms.txt file automatically with one click, pointing language models like ChatGPT to your most important content. Yoast picks the pages, or you choose them yourself, and it works in WordPress and in Yoast SEO for Shopify.
The feature is built into Yoast and free for everyone. Support for llms.txt across AI engines is still patchy, so treat it as a cheap extra on top of readable HTML.
Choose it if: you run WordPress or Shopify and want the file in place in two minutes.
5. Screaming Frog SEO Spider: best for when you need to audit a whole site
Screaming Frog crawls your site and, with JavaScript rendering switched on, uses Chrome to render each page and compare raw and rendered HTML side by side. That shows which pages hide content from crawlers that don't run scripts, page by page across the site.
The free version crawls up to 500 URLs, and a licence costs £199 a year.
Choose it if: you have hundreds of pages and need a list of every one that crawlers can't read.
How to make your site readable by AI crawlers this week
- Check your top pages first. Run your home page, pricing page, and best blog post through a bot view and note anything that are missing from the raw HTML.
- Put content in the server's HTML. None of the major AI crawlers ran JavaScript in late 2024 crawler traffic, so server-side rendering or a static build is the real fix.
- Separate search bots from training bots. Sites that opt out of OAI-SearchBot won't show in ChatGPT search answers, so block training bots if you like, and let the search bots in.
- Check your firewall. A bot rule can turn crawlers away before robots.txt comes into it, so test with a crawler user agent.
- Add an llms.txt file. It takes minutes, and it gives AI tools a map of your key pages.
- Write pages worth quoting. Readable is step one, so tighten the copy with the AI slop cleaner and follow the robots.txt for AI setup that suits your goals.
Frequently asked questions
What is the best tool to make a website readable by AI crawlers?
Start with a free check like Contengi's AI bot view to see what crawlers get. If content is missing, Prerender.io fixes JavaScript apps without a rebuild, and Cloudflare controls which bots get in.
Can ChatGPT read JavaScript websites?
OpenAI's crawlers download your HTML and don't run the scripts, so content that loads in the browser can be invisible to them. Google's crawler renders JavaScript, which is why a page can rank on Google and still be blank to ChatGPT.
Do I need an llms.txt file?
It helps a little and costs almost nothing. Readable HTML, sensible robots.txt rules, and clear content come first, and an llms.txt file is a useful extra once those are in place.
Should I block AI crawlers in robots.txt?
That depends on your goals. Blocking training bots keeps your content out of future model training, while blocking search bots like OAI-SearchBot keeps you out of AI answers, which few businesses want.
How does Contengi help with AI crawlers?
The free AI bot view shows what crawlers read and what they miss, and LLM tracking shows whether AI engines mention you. Contengi then writes well-structured content worth citing, while rendering fixes stay with your developer or a tool like Prerender.io.