Meta tag checker
Paste a URL and see every tag in its head, what Google and social apps will do with them, and what to fix first.
How to read the results
Fail means something that stops a feature working: a noindex you may not intend, two conflicting canonicals, a relative og:image URL that crawlers cannot load, an SVG share image that X will not display. Warn is worth fixing but not broken, such as a title that will be cut on desktop or a missing viewport tag. Info notes are optional extras.
The checker sees the page the way a link-preview bot does: one request, raw HTML, no JavaScript. That is deliberate. If a tag only exists after your JavaScript runs, Slack and LinkedIn will never see it.
Fixing the usual problems
- Missing Open Graph tags: generate a full set with the Open Graph generator.
- Title or description cut off: rework them with the title tag checker and meta description checker, which show where the cut falls on desktop and phone.
- Unexpected noindex: see the robots meta tag guide. Staging-site noindex tags that ship to production are one of the most common causes of pages vanishing from Google.
- Canonical pointing elsewhere: the canonical tag checker explains when that is right and when it is a bug.
Questions
What does the meta tag checker look at?
The title, meta description, robots rules (including the X-Robots-Tag HTTP header), canonical links, viewport, charset, html lang, favicon links, every Open Graph property and every twitter: tag. Each gets a pass, warn, fail or info note based on Google Search Central, the Open Graph protocol and X's cards documentation.
Why does the checker say a tag is missing when I can see it in my browser?
The checker reads the HTML your server sends, without running JavaScript, which is how Facebook, LinkedIn, Slack and X fetch pages. If your tags are injected by client-side JavaScript, social crawlers will not see them either. Google can render JavaScript, but its documentation recommends against relying on JavaScript to inject or change meta tags.
Can it check a site on localhost or behind a login?
No. For security the fetcher only reaches public http and https addresses on the standard ports. Use the Paste HTML option for staging, intranet or local pages.
Is a warning about title length an error?
No. Google has no length limit and will simply truncate a long title to fit the screen. The warning tells you roughly where the cut falls so you can make sure the important words come first.