Open SEO Crawler

Open SEO Crawler is a self-hosted, open-source crawler for technical SEO audits. It is best suited to SEO professionals, developers, and site owners who want to inspect sites locally, including for migrations or competitor research. Its unlimited-URL free plan is attractive, but using it means installing and running the software yourself.

Overview

This is a focused crawler rather than an all-in-one SEO suite. It combines a broad set of technical checks with CMS-aware recommendations, optional JavaScript rendering, and export tools. Local operation without accounts, telemetry, or API calls is a meaningful advantage for privacy-conscious teams; the trade-off is that the crawler is not a hosted service that manages the work for you.

The default crawl is capped at 1,500 pages, with five workers, a 0.4-second delay per host, and depth 10. The page cap can be changed to unlimited, so the default is a starting point rather than a hard ceiling. The README reports a 1,500-page WordPress site finishing in under three minutes with those default worker and delay settings; treat that as a reference for that setup, not a promise for every site.

Key features

Checks cover page titles, meta descriptions, H1s, canonicals, structured data, redirects, HTTP errors, indexability, hreflang, mobile viewports, mixed content, images, and security headers. That range makes it useful for finding common technical problems in one pass, especially during site audits and migrations. It does not replace broader tools for SEO work beyond crawling and technical inspection.

CMS detection spans Shopify, WordPress, Webflow, Wix, Squarespace, Kajabi, Ghost, Drupal, HubSpot, and Joomla, with crawl recommendations tailored to the detected platform. This can make results more relevant to the site being audited. Optional Playwright rendering supports JavaScript-heavy pages, and compare mode identifies content missing from raw HTML—valuable when the rendered page may differ from its source.

Bulk reports can be exported to XLSX, and sitemap export is also supported. These options make it easier to carry crawl findings into spreadsheets or retain a sitemap, though the documented export formats are not a substitute for a full reporting platform.

Pricing

The Open SEO Crawler plan costs nothing. It is free and MIT-licensed, self-hosted, and offers unlimited URLs without an account, API key, or per-URL billing. There is no free trial because the free plan is the product's stated offering. The unlimited URL allowance is especially useful for large crawls; the cost is the responsibility of installing and operating it locally.

Platforms

Installers are documented for Linux Mint, Ubuntu, and Debian; macOS 11 or newer on Intel and Apple Silicon; and Windows 10/11. The software is self-hosted and also categorized for web use, but the documented installation paths center on those desktop operating systems.

Who it's for

SEO professionals, developers, and site owners who need local technical audits, migration checks, or competitor research are the clearest fit. It is particularly compelling when URL limits or account requirements are undesirable. Readers who want a managed, browser-based service or a broader SEO suite should consider other tools instead.

Pros and cons

• Pros: Unlimited URLs and no per-URL billing make extensive crawls possible without moving to a paid tier.
• Pros: Broad technical checks, CMS-aware recommendations, and optional JavaScript rendering cover varied audit needs.
• Pros: Local execution without accounts, telemetry, or API calls offers stronger operational privacy.
• Pros: XLSX reports and sitemap export provide practical ways to use crawl results elsewhere.
• Cons: Self-hosting requires installation and local operation rather than delegating crawls to a hosted service.
• Cons: Default settings cap crawls at 1,500 pages and depth 10; larger jobs require changing the configuration.
• Cons: Its focus is crawling and technical audits, not a complete SEO suite.

Alternatives

Lighthouse is another free, open-source option for automated web page audits; choose it when that page-audit focus better fits your task.

Checkbot suits readers who prefer a browser extension and want unlimited crawls and sites on its free Basic plan, accepting a 100-URL cap per crawl and ads.

Screaming Frog SEO Spider is worth considering when a 500-URL free crawl cap is sufficient or when you want its paid licence for unlimited URLs.

WebSite Auditor offers a free option capped at 500 URLs and one project, with no paid report exports; choose it if that smaller project scope fits.

A1 Website Analyzer is an alternative for macOS and Windows users who want a free mode after a 30-day evaluation period, with a 500-page-URL-per-website allowance.

Beam Us Up is another free crawler with no limits stated.

Crab is a free, open-source crawler for Linux, macOS, and Windows.

FreeCrawl is another free option with unlimited URLs and self-hosted support.

Browse more options in SEO Audit Software, SEO Crawler Software, and SEO tools.

Verdict

Open SEO Crawler is a strong choice for SEO professionals, developers, and site owners who want broad local audits without URL-based charges. Its combination of unlimited crawling, CMS-aware checks, and optional rendering is the main reason to choose it. Look elsewhere if you need a hosted workflow or a more comprehensive SEO platform.