The paid SEO tool market is dominated by Ahrefs, Semrush, and Moz — all genuinely useful, all expensive. But before you commit to a subscription, these free tools cover a lot of ground.
Google Search Console — The Most Important One
If you only use one SEO tool, make it Search Console. It shows you exactly which queries drive clicks to your site, average position, CTR, and which pages have indexing issues. No third-party tool has access to this data because it comes directly from Google.
Set it up properly: verify your domain-level property, submit your sitemap, and check the Coverage report monthly. The Queries report alone tells you what content to write next and which existing pages to improve.
Screaming Frog SEO Spider (Free Tier)
The free version crawls up to 500 URLs — enough for most small sites. It finds broken links, redirect chains, missing meta descriptions, duplicate page titles, and pages blocked from indexing.
Ahrefs Webmaster Tools
Free with domain verification. Gives you a site audit, backlink data for your own domain, and organic keyword rankings. The backlink data alone is useful — knowing who links to you is data Search Console doesn't provide.
PageSpeed Insights
Built on Lighthouse and backed by real-world CrUX data. Pay attention to the field data at the top of the report — that's what Google's Core Web Vitals ranking signal actually measures.
When to Go Paid
Once you're billing for SEO work, free tools aren't enough. You need keyword research data, competitor gap analysis, and rank tracking. At that point a paid tool pays for itself quickly.