Crab
Crab is a free desktop SEO crawler for auditing websites on Linux, macOS, and Windows.
What Crab is
Crab is a free desktop SEO crawler for auditing websites on Linux, macOS, and Windows. It checks broken links, redirects, titles, meta descriptions, robots directives, hreflang, duplicate content, and structured data. For JavaScript sites, it can use headless Chrome to render pages, including React and Vue applications. Crab maps URL hierarchy and crawl depth, displays page relationships in an interactive link graph, and identifies orphan pages. It can also generate a downloadable XML sitemap from crawled URLs. Accessibility checks include image alt text, form labels, and heading hierarchy, with a score from 0 to 100 for each page. Projects can schedule crawls hourly, daily, weekly, or using a custom cron expression with timezone support. Crawl data is processed and stored on the user's machine; Crab says it is not sent to its servers or third parties. The open-source app is available through macOS DMG, Windows EXE, and Linux tar.gz installation instructions.
Good
- Free forever with no URL limits
- Renders JavaScript sites with headless Chrome
- Reports orphan pages and maps crawl depth
- Schedules recurring crawls with timezone support
- Processes crawl data on the user's machine
Watch out
- Google Analytics and other integrations are listed as “Soon”
- Provided as-is without warranty
- Terms require permission to crawl sites
Who it suits
Crab suits site owners and SEO practitioners who want desktop crawls, including JavaScript rendering, site-structure mapping, and accessibility checks. Its terms ask users to crawl only sites they own or have permission to crawl.
Verdict
Crab combines technical SEO checks, accessibility scoring, and recurring crawls in a free desktop app. Its local data handling and open-source code may suit users who prefer desktop crawling, but review the crawl-use terms first.
Plans and prices
From Crab's own pricing page, checked 8 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Free | Free | No URL limits · no subscriptions · no premium tiers · Free forever |
The facts
Each one read from Crab's own pages, with the date it was checked.
What it does
- Accessibility
- Crab checks items including image alt text, form labels, and heading hierarchy, then assigns each page an accessibility score from 0 to 100.checked 8 Oct 2026
- Crawl checks
- The audit suite checks broken links, redirects, titles and meta descriptions, robots directives, hreflang, duplicate content, and structured data.checked 8 Oct 2026
- Exports
- Crab can generate a downloadable XML sitemap of crawled URLs.checked 8 Oct 2026
- Installation
- The download page offers macOS DMG, Windows EXE, and Linux tar.gz installation instructions; it says the macOS app is signed and notarized by Apple.checked 8 Oct 2026
- Integrations
- The maker's comparison page lists Google Analytics, Search Console, PageSpeed Insights, and other integrations as “Soon.”checked 8 Oct 2026
- JavaScript rendering
- Crab can render JavaScript sites with headless Chrome, including React, Vue, and other single-page applications.checked 8 Oct 2026
- Local processing
- Crab processes and stores crawl data on the user's machine, and says crawl data is not sent to its servers or third parties.checked 8 Oct 2026
- Open source
- Crab is open-source software with source code available on GitHub.checked 8 Oct 2026
- Privacy analytics
- The desktop app uses PostHog for anonymous product analytics; the policy says these events exclude crawl data, website content, and personally identifiable information.checked 8 Oct 2026
- Product
- Crab is a desktop SEO crawler for auditing websites.checked 8 Oct 2026
- Recurring crawls
- Projects can schedule crawls hourly, daily, weekly, or with a custom cron expression and timezone support.checked 8 Oct 2026
- Site audit
- Yeschecked 20 Sep 2026
- Site structure
- Crab maps URL hierarchy and crawl depth, shows page relationships in an interactive link graph, and reports orphan pages.checked 8 Oct 2026
- Support
- The homepage directs users with questions to GitHub.checked 8 Oct 2026
- Terms
- The terms ask users to crawl only sites they own or have permission to crawl, respect robots.txt and crawl delays, and state the app is provided as-is without warranty.checked 8 Oct 2026
Money
- Free plan
- Yeschecked 20 Sep 2026
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