Free HTML SEO Checker

The free HTML SEO checker examines the source you paste into this page. It identifies titles, descriptions, canonical links, indexing directives, headings, image alt attributes, viewport metadata and a social preview image. It runs locally in your browser.

How to Use the HTML Checker

Open the public page you want to review and choose View Page Source in your browser. Copy the source, enter that page's URL above and paste the HTML. Select Check HTML to review the findings.

The URL provides context for relative canonical links. The tool never requests that URL. Load example supplies a deliberately imperfect page so you can try the checks without copying your own source.

Download the findings as a Markdown file to edit in any text editor. Clear removes the current inputs and results. Refreshing or closing the page also clears them; the checker does not save your source.

What Does the Checker Inspect?

Each finding reports observed markup and a next step. Observed means an element was found; Review means a human should investigate; Not checked means the input did not support that check.

• Title and description: presence, duplicates and actual text.
• Canonical: count, URL syntax and its relationship to the supplied page URL, including a declared base URL.
• Robots metadata: robots and googlebot tags, including noindex and none directives.
• H1: count and the first heading's text.
• Images: missing versus empty alt attributes. Empty alt can be appropriate for decoration.
• Viewport and social preview: a device-width viewport declaration and og:image content.

The checks follow the distinctions in Google's title guidance, canonical documentation and robots metadata documentation.

What Does This Free Check Leave Out?

This is a source review, not a live crawl. It cannot measure speed, validate SSL, read HTTP response headers, fetch robots.txt, inspect Google-selected canonicals or confirm indexation. JavaScript-generated content is only included if you paste rendered markup. Partial HTML produces partial findings.

A noindex directive can be intentional. A different canonical can be correct. Multiple H1 elements are a review prompt rather than proof of a ranking penalty. Assess each result against the page's purpose before changing anything.

Use the 50-check manual PDF for wider coverage or the editable agency toolkit to assign actions. Our documented self-audit shows how we connect evidence to fixes.

Professional support can include evidence that pasted source cannot provide. Review the scope and enquiry process on our website audit services page.