Most free SEO checkers are lead-capture forms wearing a tool costume. You paste a URL, you get a number, and the number is there to make you feel bad enough to book a call. This one just runs the checks and tells you what it found. No signup, nothing stored, no email gate.
What it is actually checking.
It fetches the page the way a crawler would, then reads the markup that search engines care about. Nothing here is exotic. It is the list you would run by hand on a launch day if you had the time, which is precisely why it is worth automating.
- Whether a title tag and meta description exist at all, which decides how the page is presented in search results
- Exactly one H1, and headings that go in order rather than jumping from an H2 to an H4
- Whether the page is actually indexable, which means no noindex directive and no robots.txt rule quietly blocking the path
- The canonical URL, and whether it points at this page or somewhere else
- Open Graph tags, because a page without them turns every share into a bare grey link
- A mobile viewport, alt text coverage, a declared language, structured data, and the raw HTML weight
A page can be beautiful, fast, and completely invisible. Indexability is binary and it beats every other optimization on this list, because nothing else matters if the page is not allowed in the index.
The two results people are usually surprised by.
The first is noindex left on after a launch. It happens constantly. A site gets built on a staging domain with indexing switched off, then goes live with the switch still flipped, and nobody notices for a month because the site looks perfect. It just is not in Google.
The second is the canonical pointing at the wrong URL. Usually a template hardcodes it, so every page on the site declares itself a copy of the homepage. Google believes you. Then people wonder why only the homepage ranks.
What it deliberately does not do.
It grades one page, not a whole site, and it reads the HTML your server returns rather than running your JavaScript. If your content only appears after a client-side render, this tool will not see it, and neither will some crawlers, which is worth knowing on its own.
It also does not measure speed. Core Web Vitals are a field measurement taken from real visitors over a 28 day window, so no instant checker can honestly tell you your LCP from one request. That is a separate job and I wrote it up in Core Web Vitals on client sites.
Make it something yours.
Explore Seedly's software and the guides to help you get started.
Explore the codebasesWhy this exists.
Every one of these checks is something that should be impossible to get wrong. A platform that ships a title tag, a canonical, Open Graph tags and a sitemap on every page by default turns this entire list into a non-event. That is how Seedly Sites handles it, and honestly the best outcome for this tool is that you run it on a client site, get an A, and never think about it again.
If you are running the checks by hand across a book of client sites, the fleet version of that problem is in managing many client websites from one dashboard, and the per-launch list is in the client website launch checklist.
Run it on your worst client site. That is where the surprises are.
