A website crawler for SEO is a tool that visits your pages, reads their content and structure, and uses that to find problems—missing titles, broken links, redirect chains, and more. If you're looking for a website SEO audit tool or want to understand how website crawler SEO works, this post covers the basics and what to look for.
How does a website crawler work for SEO?
Crawlers don’t browse like a human; they request URLs and parse the response. A typical flow:
- Discovery – The crawler gets a list of URLs to start from. Often that’s your sitemap (e.g.
yoursite.com/sitemap.xml), or it follows links from a seed set of pages. Sitemap-based discovery is usually better for coverage on larger sites. - Fetch – For each URL, the crawler sends an HTTP request and records status codes, redirects, and the HTML (and sometimes other resources).
- Extract – It pulls out the things that matter for SEO: title, meta description, headings (H1, H2, …), links, canonical tags, robots directives, structured data, and so on.
- Evaluate – It checks for issues: missing or duplicate titles, broken links, redirect chains, thin content, or pages that tell search engines not to index.
The result is a list of URLs with their SEO-relevant data and a list of issues you can fix. Many tools also store snapshots over time so you can see when something changed.
What to look for in a website SEO audit tool (crawler)
When you’re choosing a website crawler for SEO or a website seo audit tool, focus on:
- Discovery method – Does it use your sitemap? That’s the most reliable way to ensure all important pages are included. If it only follows links, some sections might be missed.
- Issue coverage – Does it flag the issues you care about: meta tags, headings, links, redirects, indexing directives, structured data? The best tools explain why each issue matters and how to fix it.
- Frequency – Can you run crawls on a schedule or after deploys? Ongoing monitoring helps you catch regressions quickly instead of discovering them in a one-off audit months later.
- Rate and limits – A good crawler respects rate limits and doesn’t hammer your server. Check whether you can tune speed or concurrency, especially on shared hosting.
If your platform doesn’t expose a sitemap, see Where to find your sitemap and Why you need a sitemap for practical options.
How maptrics uses a website crawler for SEO
maptrics is a website SEO audit tool that crawls your site using your sitemap. We discover every URL from the sitemap, fetch and analyze each page, and detect issues like missing or duplicate meta tags, broken links, redirect chains, and problems with headings or structured data. We store snapshots so you can see history and track a health score over time. We re-crawl on a schedule and can run crawls after deploys so you see new issues soon after they’re introduced.
So when we say we “crawl” your site, we mean: we read your sitemap, request those URLs, extract the SEO signals, and report what’s wrong and what improved. You can add your site to maptrics and run a first crawl to see the results.
For more on what an audit tool does with that crawl data, see What is an SEO audit tool (and what to look for). For how we combine crawling with search performance, see SEO rank tracking software: what to look for.