Site audit
Crawl any website for technical SEO issues
Enter a website and our crawler follows its links the way a search engine does, up to 500 pages. It records the exact status code of every URL and every redirect hop, then runs 117 technical SEO checks: broken pages and links, redirect chains, canonicals, duplicate titles, orphan pages, sitemaps, hreflang, structured data and which AI crawlers can get in.
- 117 technical checks
- Exact status codes
- Fixes for Claude or any coding agent
Free: the crawl runs on our own crawler, not on paid lookups. What it costs
Errors, warnings and notices
Every issue found, worst first: errors that hurt crawling and indexing, warnings worth fixing and notices to know about. Open one to see the pages it affects and the links behind it.
Status codes, redirects and click depth
The crawler fetches every URL itself, so a 301 is a 301 and a 404 is a 404. See status codes by click depth, every hop of a redirect chain and how long each page takes to answer.
Every page and link it found
Each page with its status, title, depth, response time, incoming links and internal PageRank. Filter by status code, sort by what matters and open one to see the links in and out.
Exports for Claude and coding agents
Download every issue as CSV files in one zip, with the links behind each, or as one fix brief: issues worst first, why each matters, how to fix it and the pages grouped by template, so your coding agent fixes the template once.
How it works
How to use the site audit
- 1
Enter a website
Its address, and how many pages to crawl, up to 500. Robots.txt is respected.
- 2
Let it crawl
It follows links and sitemaps, then runs every check. A few hundred pages take a few minutes.
- 3
Fix and crawl again
Work through the issues or export them, then crawl again to see what is fixed.
Use it to
Site audit use cases
Find broken pages and links
Every 4XX and 5XX page and the pages that link to them, so you fix the link as well as the page.
Check a site before and after a launch
Catch redirects, noindex tags and canonicals left over from staging before search engines do.
Hand fixes to a coding agent
Give Claude, Cursor or Codex the fix brief and let it work through the issues in your codebase.
Audit a client or prospect
Crawl any site, not only your own, and walk into the call with its technical issues.
What it costs
Site audit pricing
Free. The crawl runs on our own crawler, so it costs nothing. In a project, you can also render JavaScript pages and fetch pages behind bot protection through YepAPI, only for the pages that need it and up to a cap you set.
| Part of the search | Price |
|---|---|
| Crawl of up to 500 pages | Free |
| Crawl in a project, up to 10,000 pages | Free |
| JavaScript rendering, in projects (optional) | $0.02 per page |
| Blocked pages fetched through proxies, in projects (optional) | $0.03 per page |
Search data
Start with $5 of free search data
Keyword, ranking and backlink data in OpenSEO comes from YepAPI. Sign up there and new accounts get $5 in free credit, for a limited time. That is enough to try every tool before you spend anything.
- 1
Sign up at YepAPI
New accounts get $5 in free credit, for a limited time.
- 2
Copy your API key
It is on your YepAPI dashboard once you sign in.
- 3
Paste it into OpenSEO
During account setup, or later in Settings. Every tool works from there.
The free credit is YepAPI’s limited-time offer and may end. After it, you pay YepAPI per lookup at its price. OpenSEO lists every call with its cost and a monthly limit caps what you spend. See pricing
SEO glossary
What is a web crawler?
A web crawler, also called a spider or bot, is an automated program that browses the web by requesting pages and following the links on them. Search engines use crawlers to discover content for their index; SEO tools use them to audit sites; AI companies use them to collect content for models and live answers.
Related SEO terms
Crawling is how search engines discover pages: automated bots fetch URLs and follow the links on them to find more pages.
A 404 error is the HTTP status a server returns when a requested page does not exist. It is normal, but broken links to 404s are worth fixing.
A redirect chain is when a URL redirects to another URL that redirects again, so it takes two or more hops to reach the final page.
An orphan page is a page with no internal links pointing to it, so visitors and crawlers cannot reach it by browsing the site.
A canonical tag is a link element that tells search engines which URL is the main version of a page when duplicates exist.
An XML sitemap is a file that lists the URLs you want search engines to crawl and index, with optional last-modified dates.
Robots.txt is a plain-text file at the root of a site that tells crawlers which URLs they may and may not request.
Site audit FAQ
What is the difference between a website crawler and an SEO crawler?
A website crawler follows the links of a site and fetches its pages. An SEO crawler does that and then checks what it found the way a search engine would: status codes, redirects, indexability, canonicals, duplicate content and links. This one does both.
Does it render JavaScript?
The free crawl reads the HTML each page sends, as most search engine crawlers do first, and flags pages that are empty without JavaScript. In a project, the audit can render those pages in a browser, at $0.02 a page, up to a cap you set.
Can it crawl a site that blocks bots?
It identifies itself and respects robots.txt. When a site blocks it anyway, the report says which pages were blocked. In a project, the audit can fetch those pages through YepAPI’s proxies, at $0.03 a page.
Can I schedule crawls?
Yes, in a project. Audits run weekly or monthly, up to 10,000 pages, and each is compared with the last: which issues are new, which you fixed and which titles, descriptions and status codes changed.
Can my AI assistant run it?
Yes. The OpenSEO MCP server has tools to start a site audit, read its issues and links, and get the fix brief, so Claude can crawl a site and fix what it finds.
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