On-Page SEO Checker
Paste a page's HTML and get an instant checklist: title, meta description, headings, image alt text, canonical tag and more.
Paste Your Page's HTML
Open the page, right-click and choose "View Page Source" (or press Ctrl+U / Cmd+Option+U), then copy everything and paste it below. This tool cannot fetch another site's page itself — browsers block that for sites you do not control, so pasting the source is the reliable way to check any page, including ones that are not live yet.
Paste some HTML on the left to see the checklist here.
A Real Checklist
Title length, meta description, H1 count, heading structure, canonical tag, robots directive, viewport and Open Graph tags — all checked in one pass.
Finds Missing Alt Text
Counts every image on the page and tells you exactly how many are missing alt text, rather than a vague pass or fail.
Works on Unpublished Pages
Because you paste the HTML rather than entering a live URL, this works just as well on a staging server or a page you have not published yet.
Frequently Asked Questions
Why do I paste HTML instead of entering a URL?↓
Browsers deliberately block a web page from fetching another site's raw HTML on your behalf — a security rule called CORS that every browser enforces, and this tool cannot work around. Pasting the source is the only way to check an arbitrary page entirely in your browser, and it comes with a genuine benefit: it also works on pages that are not live yet, sitting on a staging server, or on your own machine.
How do I get a page's HTML?↓
Open the page in your browser, right-click anywhere on it and choose "View Page Source" (or press Ctrl+U on Windows, Cmd+Option+U on a Mac). Select all the text that appears, copy it, and paste it into this tool.
Does this check how the page actually ranks?↓
No — it checks the on-page fundamentals: whether a title and description exist and are a sensible length, whether there is one clear H1, whether images have alt text, and a handful of other structural signals. Ranking depends on many additional factors this tool cannot see, including backlinks, overall site authority and how well the content matches what people are searching for.
Why does it flag a page with no meta description as a failure but a long one as only a warning?↓
A missing description means Google writes its own from the page content, which you have no control over and which often reads awkwardly. A description that is merely too long still gets used — Google just truncates it — so that is a smaller problem worth fixing rather than a missing field worth flagging more seriously.
Is my HTML uploaded anywhere?↓
No. The HTML you paste is parsed using your browser's built-in DOMParser and never leaves your device. Nothing is sent to a server, and nothing is stored once you leave the page.
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About This Tool
This checks the structural basics that search engines and screen readers rely on: a clear title and description, one H1, sensible heading order, alt text on images, and the handful of meta tags that control indexing and how a link previews when shared. It does not check ranking factors like backlinks or content quality, which no client-side tool can evaluate from HTML alone.
Your pasted HTML is parsed with the browser's built-in DOMParser and never leaves your device. For details on analytics and third-party ad requests, see our Privacy Policy.