Browse curated open-source SEO tools, crawlers, rank trackers and agent projects you can inspect, adapt or self-host.
Compare products ↓Open source can provide transparency and deployment control, but it also moves maintenance onto your team. This shortlist spans full products, focused utilities and agent-ready search infrastructure.
We ran these three local tools against one deliberately faulty sample on 29 September 2026. They cover complementary tasks. None required a paid API in this test.
Scroll sideways to compare all columns →
| Tool and role | Run it | License | Useful for |
|---|---|---|---|
| SiteOne CrawlerFull site crawler | Native CLI; macOS arm64 tested | MIT | Teams building an inventory of page and resource issues. |
| lycheeLink checker | Native CLI; macOS arm64 tested | MIT / Apache-2.0 | Developers checking broken links and fragments during releases. |
| Sitemap Cohort AuditorSitemap snapshot auditor | Node.js 20+ CLI; local XML files tested | MIT | Technical SEO teams reviewing sitemap changes in a release. |
An agent skill supplies instructions; an MCP server connects an agent to tools or data. Neither is automatically a standalone crawler. Check model, API and hosting charges separately when combining them.
Compare findings and download the test files → · Browse the full open-source catalog →
OpenSEO85/100 evidence score · no reviews yet · Data checked Oct 2026Open-source SEO platform for humans and AI agentsOpen-source codeOpen Source↗02
SEO & GEO Skills85/100 evidence score · no reviews yet · Data checked Oct 202620 production workflows for modern search optimizationOpen-source codeSkill↗03
Toprank85/100 evidence score · no reviews yet · Data checked Oct 2026SEO and paid acquisition skills for Claude CodeOpen-source codeSkill↗04
OpenSERP85/100 evidence score · no reviews yet · Data checked Oct 2026Open-source SERP API for SEO and AI automationOpen-source codeOpen Source↗05
SEO Skill84/100 evidence score · no reviews yet · Data checked Oct 2026One skill and 50+ audit tools for AI agentsOpen-source codeSkill↗06
DataForSEO MCP84/100 evidence score · no reviews yet · Data checked Oct 2026Official MCP access to professional SEO dataOpen-source codeMCP↗07
DigestSEO84/100 evidence score · no reviews yet · Data checked Oct 2026Open-source Search Console for AI visibilityOpen-source codeOpen Source↗08
SEOnaut84/100 evidence score · no reviews yet · Data checked Oct 2026Simple, self-hosted technical SEO auditingOpen-source codeOpen Source↗09
SerpBear84/100 evidence score · no reviews yet · Data checked Oct 2026Open-source rank tracking with unlimited keywordsOpen-source codeOpen Source↗10
Unlighthouse79/100 evidence score · no reviews yet · Data checked Oct 2026Run Lighthouse performance scans across an entire siteOpen-source codeOpen Source↗11
SiteOne Crawler78/100 evidence score · no reviews yet · Data checked Oct 2026Cross-platform audits for SEO, security and accessibilityOpen-source codeOpen Source↗12
Firecrawl MCP78/100 evidence score · no reviews yet · Data checked Oct 2026Search, crawl and extract clean web data from AI agentsOpen-source codeMCP↗Open-source code does not mean free data or hosting. Check the project license and any API, cloud or infrastructure costs before choosing.
Open a listing for features, compatibility, screenshots and direct links.
Open-source SEO platform for humans and AI agents
Keyword research, rank tracking, backlinks, technical audits and AI visibility in one self-hostable workspace. Includes an MCP endpoint and reusable agent skills. Its documented capabilities include Keyword and competitor research, Technical SEO audits and AI visibility tracking.
20 production workflows for modern search optimization
A broad collection of reusable SEO and GEO workflows covering research, technical audits, content planning and AI search visibility. Its documented capabilities include Keyword research, Competitor analysis and Technical SEO. It is most relevant to workflows involving Agent Skills and GEO.
SEO and paid acquisition skills for Claude Code
Open-source agent workflows connected to Search Console, Google Ads and Meta Ads with actionable technical SEO recommendations. Its documented capabilities include GSC analysis, Technical audits and Google Ads insights. It is most relevant to workflows involving Agent Skills and Search Console.
Open-source SERP API for SEO and AI automation
A normalized API and CLI for live results from multiple search engines, including answer boxes, related searches and AI summaries. Its documented capabilities include Multiple search engines, Normalized JSON API and SERP feature extraction.
One skill and 50+ audit tools for AI agents
A developer-focused SEO audit toolkit that helps coding agents find, explain and fix organic and AI search visibility issues. Its documented capabilities include 50+ audit utilities, Typed crawler and Actionable reports. It is most relevant to workflows involving Agent Skills and SEO Audit.
Official MCP access to professional SEO data
The official DataForSEO MCP server exposes SERPs, keywords, backlinks, on-page audits and AI optimization data to compatible agents through a maintained TypeScript implementation. Its documented capabilities include SERP endpoints, Keyword data and Backlink analysis.
Open-source Search Console for AI visibility
Monitor which AI engines cite your brand, the prompts you win and where competitors are gaining visibility. Its documented capabilities include AI citation monitoring, Prompt tracking and Competitor gaps. It is most relevant to workflows involving GEO and AI Visibility.
Simple, self-hosted technical SEO auditing
A mature open-source crawler that discovers broken links, redirect problems, metadata issues and structural SEO errors. Its documented capabilities include Full-site crawler, Issue severity scoring and Redirect analysis. It is most relevant to workflows involving Technical SEO and Crawler.
Open-source rank tracking with unlimited keywords
Track Google positions across domains with Search Console data, email notifications and a built-in reporting API. Its documented capabilities include Unlimited keyword tracking, GSC integration and Notifications. It is most relevant to workflows involving Rank Tracking and Search Console.
Run Lighthouse performance scans across an entire site
Unlighthouse combines site crawling with Lighthouse to scan many pages, visualize performance and accessibility results, and run locally or in continuous integration. Its documented capabilities include Site-wide Lighthouse scans, Performance dashboards and Route discovery.
Cross-platform audits for SEO, security and accessibility
SiteOne Crawler analyzes websites for technical SEO, security, accessibility and performance issues through a cross-platform CLI and desktop-friendly reporting workflow. Its documented capabilities include SEO and link audits, Security checks and Accessibility analysis.
Search, crawl and extract clean web data from AI agents
The official Firecrawl MCP server adds live search, scraping, crawling, mapping and structured extraction tools to MCP-compatible agents with cloud and self-hosted options. Its documented capabilities include Web search, Page scraping and Site crawling.
Short answers to the questions that matter most for this workflow.
Not necessarily. The code may be available without a license fee, but hosting, proxies, APIs, storage and maintenance can still cost money.
Review the license, recent maintenance, security model, data storage, external API dependencies and the resources required for updates and backups.
It depends on the project license. Always check the repository license and any third-party service terms before commercial deployment.