Guide

The Complete Guide to Free Online SEO Tools

Most SEO work happens in the ten minutes before a page goes live — writing the title, checking how the share card will look, making sure the right things are crawlable. It is quick, easy to get wrong, and usually invisible until something looks broken in public. These tools cover that window, and every one of them runs in your browser, which matters when the pages you are working on are unreleased.

Free foreverNo sign-upRuns in your browser
01

Write meta tags and see them before you ship

Google truncates titles and descriptions by rendered pixel width, not character count — which is why character counters mislead. A title made of narrow letters genuinely fits more characters than one full of capitals. The Meta Tag Generator measures the real width and shows a live Google result preview alongside social card previews, so you see what will actually appear. When a share is already broken, the Open Graph Preview reads your existing tags and tells you why: a missing image, or a relative path that social crawlers cannot resolve.

02

Add structured data without hand-writing JSON-LD

Rich results need valid structured data, and the schema is fiddly to write by hand. The Schema Markup Generator builds JSON-LD for Article, FAQ, Product, LocalBusiness, Breadcrumb, HowTo and Organization, flagging the fields Google requires before a page is eligible at all. Only mark up content that is actually visible on the page — describing things a visitor cannot see is a manual-action risk.

03

Control crawling, and test that it works

robots.txt precedence is longest-match, not first-match, with Allow beating Disallow on a tie. That catches people out constantly, and a generator alone will not tell you. The Robots.txt Generator includes a tester: give it a URL and a crawler, and it names the rule that actually decides. The XML Sitemap Generator turns a URL list into a valid sitemap, deduplicating and validating as it goes — it cannot crawl your site to find those URLs, because browsers block cross-origin requests, and any tool claiming otherwise is running a server.

04

Survive a migration

Site migrations lose traffic for one reason: old URLs stop working and nothing tells search engines where the content went. The Redirect Generator turns a migration map into Apache, Nginx, Netlify or Vercel rules and flags the two things that actually cause damage — loops, which break the page outright, and chains, where each extra hop costs crawl budget and a little link equity. Map each old URL to its closest equivalent rather than to the homepage; bulk-redirecting everything to the root preserves almost nothing.

05

Check the content itself

The Readability Checker runs six standard formulas at once and is honest that syllable-based scores are estimates rather than measurements. The Keyword Density Analyser is equally blunt: there is no density target and no search engine rewards one. What it is genuinely good for is showing what a page is actually about, which is often not what you intended — and spotting a phrase repeated so often a reader would notice. The UTM Campaign Builder normalises case, which stops one campaign being split across several rows in your analytics.

From reading to doing

Put it into practice.

Every tool in this guide is free, private, and runs entirely in your browser.

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