Sitemap Verifier
Check your sitemap.xml for issues that hurt SEO and AI crawl coverage.
Validates structure, finds duplicates, missing lastmod, oversize files, and more.
Built by the RenderBeam team — we render JS sites for crawlers in production. · Updated May 2026.
Tip: you can paste just a domain (e.g. example.com) — we'll auto-detect /sitemap.xml and /sitemap_index.xml.
What is a sitemap?
An XML file listing the URLs you want crawlers to discover, with metadata like last-modified dates.
Common issues
Malformed URLs, missing lastmod, files over 50MB or 50k URLs, duplicate entries.
Why it matters for AI
AI crawlers (GPTBot, PerplexityBot, ClaudeBot) use sitemaps too. A broken sitemap means missed indexing.
How this checker works
We fetch your sitemap server-side from a public IP using the User-AgentRenderBeam-SitemapVerifier/1.1and apply the official sitemaps.org protocol rules:
- Detects whether the file is a
<urlset>or a<sitemapindex>. - Counts
<loc>entries and checks each is a valid absolute URL ≤ 2,048 chars. - Flags duplicate URLs (wasted crawl budget).
- Measures
<lastmod>coverage — Google uses this for re-crawl prioritization. - Enforces Google & Bing limits: 50,000 URLs and 50 MB uncompressed per file.
- Transparently decompresses
.xml.gzsitemaps (with a 50 MB safety cap to prevent gzip bombs). - Auto-tries
/sitemap.xmland/sitemap_index.xmlwhen you paste a bare domain.
Privacy & safety
We don't store your sitemap content or the URLs inside it. Each request is fetched once, analyzed in memory, and discarded. We block requests to private/internal hosts to prevent abuse, cap downloads at 5 MB on the wire and 50 MB after decompression, and identify ourselves with a clear User-Agent so site owners can attribute the traffic.
Frequently asked questions
What is a sitemap.xml?
A sitemap is an XML file at the root of your site that lists the URLs you want crawlers (Google, Bing, GPTBot, ClaudeBot, PerplexityBot) to discover, optionally with last-modified dates, change frequency, and priority hints.
How big can a sitemap be?
A single sitemap file can contain at most 50,000 URLs and 50 MB uncompressed. Above that, split it into multiple files referenced by a sitemap index (sitemap_index.xml). Both gzipped (.xml.gz) and plain XML are supported.
Do I really need <lastmod>?
Yes — Google has confirmed it uses <lastmod> as a signal for re-crawl prioritization, but only if the value is accurate. Don't update it on every deploy if the page didn't actually change.
Do AI crawlers use sitemaps?
Yes. GPTBot, ClaudeBot, PerplexityBot, and Google-Extended all read sitemap.xml the same way classical search bots do. A broken sitemap means missed coverage in AI answers.
Does this tool store my sitemap or URL?
No. The URL is fetched once on our edge, analyzed in memory, and discarded. We log only the host, status, and timing for abuse-prevention — never the URLs inside the sitemap.
A clean sitemap only helps if bots can render your pages
If your site uses React, Vue, or any JS framework, most crawlers see a blank page. RenderBeam fixes that — pre-rendered HTML for every bot in your sitemap.
Try RenderBeam FreeGo further with RenderBeam
Keep going — here are a few good next stops.