Tool category
Free Utility
Free, single-purpose utilities. Often the fastest answer to a narrow question.
12 tools · 12 free or with a free tier · 33 more cover this area as a secondary feature
| Tool | What it does | Pricing | From | HQ |
|---|---|---|---|---|
| advertools advertools.readthedocs.io | Open-source Python library for SEO and SEM workflows, including crawling with Scrapy, robots.txt and sitemap parsing, SERP APIs, log file parsing and text analysis. | Open Source | — | — |
| Aizhan aizhan.com | Chinese webmaster tool site providing composite SEO diagnostics, Baidu weight and keyword ranking analysis, backlink and reciprocal-link checks, keyword mining, dead-link detection and historical site data, plus a paid data API. | Freemium | — | China |
| Chinaz Webmaster Tools chinaz.com | Chinese webmaster tool suite from Chinaz covering SEO overview queries, Baidu weight estimation, app and site ranking lookups, WHOIS, ICP filing checks, reciprocal-link verification and a data API. | Freemium | — | China |
| Google robots.txt Parser github.com | Google's own robots.txt parser and matcher released as an open-source C++11 library, used as the reference implementation of how Googlebot interprets robots.txt directives. | Open Source | — | United States |
| Greenflare SEO Crawler greenflare.io | Free and open-source desktop SEO crawler for Linux, macOS and Windows that performs technical audits and exports crawl data. | Open Source | — | — |
| Hreflang Tags Generator aleydasolis.com | Free tool by Aleyda Solis that builds valid hreflang annotations for HTML, HTTP headers or XML sitemaps from a list of localised URLs. | Free | — | Spain |
| httpstatus.io httpstatus.io | Free bulk URL checker that reports HTTP status codes and full redirect chains for lists of URLs. | Freemium | — | — |
| LinkChecker linkchecker.github.io | Open-source Python command-line tool that checks links in web documents or across full websites, with recursive crawling, several output formats and an optional WSGI web interface. | Open Source | — | — |
| Pytrends github.com | Unofficial open-source Python client for Google Trends, used to pull interest-over-time, regional interest and related query data programmatically. | Open Source | — | — |
| SEO Review Tools seoreviewtools.com | Collection of 82 free browser-based SEO and AI tools including a keyword tool, rank checker, backlink checker and domain authority checker, backed by a paid SEO API. The vendor also publishes an MCP server for its API. | Freemium | — | — |
| SEODeploy github.com | Open-source Python library for running automated SEO regression checks against staging environments as part of a deployment pipeline. | Open Source | — | United States |
| TechnicalSEO.com Tools technicalseo.com | Free suite of technical SEO utilities from Merkle including robots.txt tester, schema generator, hreflang tag generator, fetch and render, and mobile-first testing. | Free | — | United States |
Also covers free utility
These tools are catalogued under another primary category but include free utility functionality.
Ahrefs SEO ToolbarBing Webmaster ToolsBlackKiwiClassy SchemaCloudflare Web AnalyticsCrUX DashboardDetailed SEO ExtensionGoogle Business ProfileGoogle Keyword PlannerGoogle Rich Results TestGoogle Search ConsoleGoogle TrendsHubSpot AI Search GraderIndexNowLighthouseLink Redirect TraceLooker StudioMerkle Schema Markup GeneratorMozBarNuxt SEOPageSpeed InsightsPlePerRedirect PathSchema Markup ValidatorSEO MinionSEO Pro ExtensionSEOquakeSerpScrapSitelinerView Rendered SourceWeb Vitals Chrome ExtensionWhatsMySERPYandex Metrica
Other categories
GEO AI Visibility (47)All In One (32)Crawler (17)Analytics (15)Content Optimization (15)Keyword Research (15)Page Speed (15)Rank Tracking (14)SERP API (13)Browser Extension (12)Local SEO (10)Reporting (10)AI Writing (9)WordPress (9)Digital PR (8)Technical SEO (7)Backlinks (6)Schema (6)Log Analysis (5)Ecommerce SEO (4)Internal Linking (4)Enterprise (3)