Free Online SEO Tools
Free online SEO tools: 28 browser-based checkers, no signup, no limits. Analyze any URL directly in your browser.
Built by Julien El-Bahy — every tool is hand-crafted, not white-labeled.
Meta Tag Analyzer
Audit title, description, canonical, robots, hreflang, and OG tags with pixel-precise SERP previews and live-edit fix suggestions.
Heading Checker
Visualize your H1–H6 hierarchy, detect skipped levels, and check heading structure for SEO best practices.
Schema Validator
Extract and validate JSON-LD structured data with deep content checks Google's own validator misses.
OG Preview
Preview your Open Graph card on 11 platforms — Facebook, X, LinkedIn, Slack, Discord, WhatsApp and more — all rendered live.
Alt Text Checker
Audit every image on a page for missing alt text, file size, modern formats, dimensions, and lazy-loading mistakes.
Semantic HTML
Check HTML5 landmarks — header, nav, main, article, section, footer — for accessibility and AI crawler readability.
Link Analyzer
Map every link on a page — internal, external, broken, nofollow — with anchor text and live status codes.
PageSpeed Insights
Run Lighthouse audits with Core Web Vitals + AI Fix Engine — generates copy-ready code for every issue, not just suggestions.
Tech Stack Detector
Identify the technologies behind any website — CMS, frameworks, analytics, CDN, and 460+ signatures.
Security Headers
Check HTTP security headers — HSTS, CSP, X-Frame-Options, Permissions-Policy — and get a security grade with fix suggestions.
Redirect Checker
Follow the full redirect chain of any URL. Detect redirect loops, mixed-content, and HTTP status codes.
Crawler Access Checker
Check which of 37 crawlers (Googlebot, GPTBot, ClaudeBot, OAI-AdsBot, PerplexityBot…) can access your site — robots.txt + live UA check.
JS vs No-JS
Compare rendered vs. raw HTML to see what content AI crawlers and older search engines miss without JavaScript.
hreflang Checker
Validate hreflang tags for international SEO. Check return links, self-references, and x-default annotations.
Sitemap Validator
Validate XML sitemaps, check URL health, detect duplicates, and get a sitemap health score with actionable fixes.
Broken Link Checker
Find 404 errors, dead links, and redirect issues. Scan any page or check up to 2,000 URLs from your sitemap.
SERP Preview
Preview your Google snippet with pixel-width counter, desktop/mobile toggle, and live keyword highlighting.
SERP Checker
Check live Google search results for any keyword. See titles, descriptions, URLs, and SERP features.
Keyword Research
Search volume, CPC, KD, AI Overview share, and trending keywords — powered by DataForSEO with real Google Ads data.
Keyword Cannibalization
Compare two keyword SERPs to find pages competing for the same query. Spot cannibalization before it costs rankings.
PAA Research
Extract Google People Also Ask questions with 4-level expansion, AI answer quality scoring, and GEO-ready content briefs.
AI Content Optimizer
Score content for SEO: keyword density, readability, semantic coverage, and AI-generated meta tags. Connects to GSC for real query data.
SEO Localization
Translate any page for a new market with DataForSEO-verified keyword volumes, top-3 competitor SERP, and copy-ready hreflang.
AI Humanizer
Detect ChatGPT/Claude tells and rewrite AI text to read human. Language-aware for English, German, French, Spanish, Italian.
llms.txt Generator
Create and validate llms.txt files that guide AI crawlers on how to index and cite your content.
Query Fan Out
See how AI search engines decompose your query into 8–12 sub-queries — and which ones your content actually answers.
GEO Readiness Checker
Audit AI crawler access, llms.txt, structured data, and content citability across 64 checks in one pass.
What are free online SEO tools good for?
The honest version: free online SEO tools cover 80% of the daily work most SEOs do. Auditing a specific page, checking a tag, validating a redirect, testing how a URL will look on social. The paid subscription tools win on historical databases and bulk analysis, but for day-to-day work, a good free stack is often enough.
How to choose a free SEO tool
Start with the task, not the tool. "I need to check my hreflang setup" points you to the hreflang checker. "I want to see my SERP snippet before publishing" points you to the SERP preview. Avoid tools that bundle 20 features into one interface. Specialized tools give you clearer output and usually update faster because the maintainer isn't spread across every SEO category at once.
Are free SEO tools reliable?
The answer depends on where the data comes from. Tools that call Google's own APIs (PageSpeed Insights, Search Console, Google Ads, Lighthouse) are as reliable as the source itself. Tools that scrape Google SERPs without a proper API tend to break when Google changes its HTML, and the data quality drops quietly between breakages. Before trusting a free tool, check its documentation for the actual data source. If it says "proprietary algorithm", be skeptical.
All 28 tools plus GSC, GA4, AI crawler checks, keyword research, and more in one Chrome extension.
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