Crab review
A free desktop crawler with unusually deep technical and structured-data audits.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Crab is a free desktop SEO crawler for technical site audits on macOS, Windows, and Linux. It is aimed at SEO professionals, students, solo founders, and others who need occasional or private website audits. The crawler checks broken links, HTTP statuses, redirects, metadata, canonical directives, robots directives, hreflang, structured data, duplicate content, accessibility, JavaScript-rendered pages, site architecture, and page performance. It also generates XML sitemaps and supports recurring crawl scheduling.
Its strongest differentiator is the depth of its technical and structured-data coverage at no cost. Crab can render JavaScript for single-page applications, detect redirect chains and loops, identify exact and near-duplicate content, validate JSON-LD, and visualize crawl depth and orphan pages. That combination makes it useful for audits where a basic link checker would not be enough. Recurring crawl scheduling adds a way to revisit technical issues, while the local desktop model supports private crawling without a subscription or URL limit.
Crab is a focused crawler rather than a broader SEO suite, so it suits buyers whose priority is technical site quality and information architecture. Its desktop-only format may be less suitable for teams seeking a browser-based, shared workspace or a wider workflow around ongoing search performance. Choose Crab when structured-data validation, JavaScript rendering, redirects, hreflang, and site hierarchy are central to the audit. Choose another category of tool when the primary need is a wider SEO platform rather than local technical crawling.
Crab pros and cons
- Where it wins
- JavaScript rendering supports audits of SPA websites.
- Validates hreflang and JSON-LD structured data.
- Visualizes hierarchy, crawl depth, and orphan pages.
- Where it doesn't
- Desktop-only workflow may not suit browser-based collaboration.
- Focused on technical crawling rather than a full SEO suite.
- Local crawling requires installing software on a supported desktop.
Crab fact sheet, pricing and score →
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