Website SEO Score Checker

Paste the HTML of any page into this SEO score checker and it grades the markup across about 25 checks covering title and description, headings, images, links, technical tags, social tags and structured data. The score starts at 100 and drops 15 points per fail and 5 per warning, with the full rule printed on screen.

How do you run this SEO score checker?

• Open the page in your browser, right click on it, and choose View Page Source.
• Select all of the source and paste it into the box above.
• Add the page URL if you want internal and external links told apart. The URL is only used for comparison and self reference. It is never fetched.
• Add a target keyword if the page is written for one. The checker then looks for that phrase in the title, in the H1, and in the first 100 words.
• Read the score, then work down the fix list under it. Every check is marked pass, warning or fail, with the fix written next to it.

The whole run happens in your browser. The HTML you paste is never uploaded to a server, so a staging page or an unpublished template is safe to test here.

How is the SEO score worked out?

There is no hidden formula. The score starts at 100, each fail takes off 15 points, each warning takes off 5 points, and every check is charged once at most. A few items are marked as info and cost nothing. The keyword appearing in the first 100 words is one of those info items, because a strong page can open with a story instead.

You can reproduce the number by hand from the check list. A score you cannot audit is a score you should not trust. The groups break down like this.

• Title and description: present or missing, inside the usual length bands, and measured in pixels against 600 px for titles and 920 px for descriptions, since results cut text by width, not by character count.
• Headings and content: exactly one H1, at least one H2, no skipped heading levels, and a word count check that flags pages under 300 words as thin.
• Images: how many images carry an alt attribute and how many are missing one.
• Links: the split between internal and external links, judged against the page URL when you provide it.
• Technical tags: a canonical that is present and absolute, plus viewport, charset, language, and a noindex check.
• Social and structured data: the basic Open Graph tags, a Twitter card, and JSON-LD that is present and parses without errors.

Why does pasting beat a live fetch for this SEO check?

Plenty of checkers ask for a URL and fetch the page from their server. That route fails on exactly the pages you most need to test. A staging build behind a login never loads for an outside fetcher. A template inside your CMS has no public URL at all. A page you have not published yet does not exist on the open web.

A paste skips all of that. You hand over the exact bytes your CMS plans to serve, copied from view source, and the checker grades those bytes.

What can this SEO score checker not see?

Here is what a paste can never show, stated plainly. Page speed and Core Web Vitals need a live load on a real device, and no pasted HTML carries timing data. The HTTP status of the live page and any redirect chain in front of it need a server request. Response headers never appear in page source. Backlinks live in indexes that other companies crawl and store, and no browser tool has access to them.

None of those checks are run here, and the page will not pretend otherwise. The score is a checklist result for the markup you pasted. It is not a Google metric, and it is not a ranking prediction. A page can score 100 and still rank nowhere, because ranking also depends on links, competition, and search intent.

When is a pasted SEO score check the right call?

Run it before a template goes live, and you catch a missing canonical or a doubled H1 while the fix still costs nothing. Run it after a plugin update, and you see straight away if the update dropped your Open Graph tags or broke the JSON-LD. Run it on a staging build during a redesign, and the fix list gets agreed before launch day instead of after.