Free tool, runs in your browser
Meta tag checker for title, description and Open Graph
This meta tag checker reads the HTML you paste and reports the title, meta description, canonical, robots, viewport, language, Open Graph and Twitter card tags, H1 count and JSON-LD blocks, with a pass, warning or fail for each. Nothing is fetched or uploaded: the HTML is parsed inside your browser.
How to use the Meta Tag Checker
- 1Open the page sourceIn your browser, open the page and press Ctrl+U (Cmd+Option+U on Mac) to view source.
- 2Copy the HTMLSelect all and copy. The head section is enough, but the full page lets the tool count H1s.
- 3Paste and checkPaste into the box and press Check tags.
- 4Fix fails firstMissing title, missing description, noindex by mistake and multiple H1s come first.
- 5Preview the social cardThe Open Graph preview shows roughly how a shared link will look.
Why paste instead of a URL?
Fetching a URL from our server would mean making requests on your behalf to any address, which is a security and privacy risk. Pasting the HTML keeps the check private and works for staging pages behind a login too.
What each check means
| Tag | Good state |
|---|---|
| title | Present, 30 to 60 characters, unique per page |
| meta description | Present, 70 to 160 characters |
| link rel=canonical | Present, absolute URL |
| meta robots | No noindex on pages you want found |
| og:title, og:description, og:image | All present for good link previews |
| twitter:card | summary_large_image for image previews |
| H1 | Exactly one |
| JSON-LD | Valid JSON with an @type |
The Open Graph protocol is documented at ogp.me. To build structured data, use the schema markup generator.
Frequently asked questions
Does the checker send my HTML anywhere?
No. The browser's built-in DOMParser reads the HTML locally. Nothing leaves your device.
Why does it say my page is client-rendered?
If the pasted source has almost no text and an empty root element, the content is probably rendered by JavaScript. Search engines can render it, but meta tags should still be in the initial HTML.
Can it validate JSON-LD against schema.org?
It checks that each block is valid JSON and has an @type. For full validation use the Schema Markup Validator at validator.schema.org.