Meta Tag Inspector

How to use Meta Tag Inspector

1. Copy the page’s HTML source, for example with View Source or curl -sL https://example.com, and paste it into Page HTML. For pages that add tags with JavaScript, copy the rendered DOM from DevTools (Elements → Copy outerHTML) instead.
2. You can also drop an .html file on the box or use Open file. Load sample fills in an example page.
3. Work through the checklist: Errors, Warnings, Suggestions and Passed checks for the title, description, canonical, robots, mobile viewport, charset, language, hreflang, icons, Open Graph, X / Twitter, structured data, headings and images.
4. Look at the Previews of a Google result, a Facebook / LinkedIn card and an X card, then the Basics, Open Graph, X / Twitter, Structured data and Headings outline panels for the raw values.

How it works

The HTML is parsed with the browser’s DOMParser into an inert document: scripts don’t run, images and stylesheets aren’t loaded, and the document is never added to the page. The tool reads the <title>, <meta> and <link rel> tags, the lang attribute, <base href>, application/ld+json scripts, headings and images, and then runs its checks on that data.

Titles of 30–60 characters and descriptions of 70–160 characters count as in range. Other checks look for a single absolute canonical URL, noindex or nofollow in the robots or googlebot meta tags, a viewport with width=device-width that doesn’t block zooming, a UTF-8 charset, valid hreflang codes with an x-default and a self-reference, og:title, og:type, og:image (absolute, with width and height) and og:url, a known twitter:card type, JSON-LD that parses as JSON (with its @type values listed), one <h1> without skipped heading levels, and images without an alt attribute.

Relative URLs are resolved against the canonical URL or og:url when one of them is absolute, taking <base href> into account. The previews use og: and twitter: values first and fall back to the title and description, truncated to roughly what each platform shows.

Limits

• Pages aren’t fetched: the site can’t make requests to other servers, so you need to paste the HTML or open a saved file.
• Only the first 5 MB of input is analysed. At most 500 meta tags, links and headings and 50 JSON-LD blocks are read, and long values are shortened.
• Tags added by JavaScript after the page loads aren’t in the View Source HTML; paste the rendered DOM to see them.
• HTTP headers such as X-Robots-Tag or a Link canonical aren’t visible in HTML and are not checked.
• Previews are approximate and images are never loaded, so image size, format and reachability aren’t checked. JSON-LD is checked for valid JSON only, not against schema.org or Google’s rich result rules.

Privacy

The HTML is parsed entirely in your browser without running scripts or loading any of the page’s images, styles or other resources. Nothing you paste or open is uploaded or stored, and the site’s Content Security Policy blocks requests to other servers.

Frequently asked questions

Can I enter a URL instead of pasting HTML?

No. The site can only talk to its own server, so it can’t download other websites. Copy the source with View Source, or run curl -sL https://example.com -o page.html and open the saved file.

Why does the tool say a tag is missing when I can see it in DevTools?

The tag is probably added by JavaScript. View Source and curl show the HTML the server sends, which is what many crawlers and link preview bots read. Paste the rendered DOM (DevTools → Elements → right-click <html> → Copy outerHTML) to check the final tags.

Why don’t the preview cards show my image?

Images are deliberately not loaded, for privacy and because the site can’t contact other servers. The card shows the resolved image URL and alt text instead.

Are the title and description length limits exact?

No. Search engines truncate by pixel width, not characters. The 30–60 and 70–160 character ranges are common guidelines, and the previews cut text at roughly the same points.

Does it validate my structured data?

Only that each JSON-LD block is valid JSON. It lists the @type values it finds but doesn’t check required properties or rich result eligibility.