Open source SEO tools are free programs you run yourself to crawl and audit your site, test page speed, find broken links and track rankings. They work on your own site's data. None of them supplies keyword search volumes or a database of who links to you, so pair them with free search engine data or a commercial suite.
There's one thing open source SEO software can't replace: the data. Keyword search volumes and an index of which sites link to which come from companies that crawl the web and sell access to the results, and no repo on GitHub hands you that. What open source tools do well is look hard at your own site, for free, as often as you like.
Here are nine of them, in no particular order, covering crawling, speed, broken links and rank tracking. Nothing's crowned, and most need some comfort with Docker, Node, Python or PHP.
The software is free; the search data comes from elsewhere
Free to run doesn't mean free of outside services. The rank tracker on this list checks positions by sending queries through third-party scraping services or your own proxy IPs. Its README lists commercial scraping providers alongside a free-key option, so the software is free while dependable rank data may not be.
The speed and audit tools measure your own site only. None of the nine gives you keyword volume or data on which sites link to you of the kind commercial SEO suites sell. For that, your own Search Console account is the free starting point, and a commercial suite fills the rest.
Nine tools and the job each does
| Tool | Job on your site | Good for |
|---|---|---|
| advertools | Python SEO library | Crawling, robots.txt and sitemap analysis from Python |
| Google Lighthouse | Page audit engine | Performance, best-practice and SEO checks on single pages |
| LinkChecker | Broken link checker | Finding broken links across a website |
| lychee | Broken link checker | Fast broken link and email checks in sites and documents |
| Seo Panel | SEO control panel | Managing SEO tasks for several websites in one panel |
| SEOnaut | Site audit crawler | Crawling a site and sorting issues by severity |
| SerpBear | Rank tracker | Tracking positions through scraping services or your own proxies |
| sitespeed.io | Performance monitoring | Measuring page speed and monitoring it over time |
| Unlighthouse | Whole-site Lighthouse scans | Running Lighthouse across a whole site at once |
Nine open source SEO tools, in no particular order
advertools
Best for: Marketers and analysts comfortable with Python who want crawling, robots.txt and sitemap functions to build their own SEO analysis at scale.
Google Lighthouse
Best for: Checking one page at a time for performance metrics, best practices and basic SEO, using the engine that whole-site scanners build on.
LinkChecker
Best for: Site owners who want a long-running GPL-2.0 tool that checks a website for broken links and does that one job.
lychee
Best for: Developers checking websites and documents for broken links and email addresses, as a command-line tool, library or GitHub Action.
Seo Panel
Best for: Agencies or owners of several sites who want a self-hosted control panel on PHP and MySQL, which its README claims was the first of its kind.
SEOnaut
Best for: Small teams wanting a self-hosted crawler that audits a site and sorts issues into critical, high and low severity.
SerpBear
Best for: Owners tracking search positions with email alerts, an API and Search Console data, who'll supply a scraping service or proxies for the checks.
sitespeed.io
Best for: Performance-minded teams monitoring page speed over time, running it from the project's own Docker images.
Unlighthouse
Best for: Site owners who want a Lighthouse scan across a whole site in one interface, with smart sampling instead of one URL at a time.
Four jobs these tools do on your own site
Crawling and auditing
SEOnaut crawls a site and sorts what it's found by severity. Seo Panel is a PHP control panel for managing several sites; its repo shows GPL-2.0. advertools is a Python library rather than an app, and it's moving at a slower pace than the others.
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Page speed and quality
Google Lighthouse checks one page at a time for performance, best practices and SEO basics. Unlighthouse runs it across a whole site, so you don't have to test URL by URL. sitespeed.io measures speed and tracks it over time.
Broken links
lychee is a fast Rust checker that also works as a GitHub Action, and LinkChecker is a long-running GPL-2.0 tool for checking websites.
Rank tracking
SerpBear tracks positions and connects to Search Console, but needs a scraping service or proxies to check rankings.
Some honest advice for running SEO tools yourself
Use open source for the jobs that only need your own site: crawling, speed, broken links and technical checks. Those tools are often as thorough as commercial ones for that work, and you're free to run them on every deploy. Don't expect them to tell you what to write about or who links to your competitors; that's a job for a keyword and link database, and it isn't one you'll solve with a repo.
If setting up Docker or Node isn't for you, a browser-based checker will cover the basics, and these free SEO checker tools need no install. For speed alone, compare the open source scanners with these website speed test tools, and if rank tracking matters most, look at local rank trackers that include the data.
A starter stack for a small site
- A crawler run monthly to catch broken pages, missing titles and redirect chains.
- A whole-site speed scan after any theme or plugin change, so slow templates show up before visitors notice.
- A link checker in your publishing routine or build pipeline, so broken links never go live.
- Search Console for the keyword and click data none of these tools supplies.
- A rank tracker only if you'll act on it, with a scraping service you trust behind it.
Do you make an open source SEO or site audit tool? Tool makers can ask to be considered for a featured place on this list.
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Frequently asked questions
Are open source SEO tools free?
The software is free to download and run. Some jobs need outside services, though: rank tracking needs a scraping service or your own proxies, and keyword volumes come from search engines or commercial data providers.
Can open source tools give me keyword search volumes?
Not on their own. Keyword volumes come from search engine data or commercial databases. Your own Search Console account shows the queries you already appear for, which is a good free starting point.
Do I need to code to use open source SEO tools?
Not always, but most need some technical comfort. Expect to install things with Docker, Node, Python or PHP, and to run some tools from the command line.
Is a self-hosted rank tracker accurate?
That's down to the scraping service or proxies behind it. The software only sends the queries; the quality of the results depends on how reliably those checks reach the search engine.
Can these tools replace a commercial SEO suite?
For technical checks on your own site, often yes. For keyword research, competitor analysis and data on who links to you, no, because that needs a large web-wide database.
How often should I run an SEO crawl?
Monthly's fine for most small sites, plus after any big change such as a redesign, a migration or a new theme. Larger sites that publish daily may want a weekly crawl.
