Open Graph checker
See what people get when your page is shared: the title, description and image of the card. The check reads every Open Graph and Twitter tag, loads the share image to measure its real size, type and weight, and tells you what to fix.
Or ask your AI assistant
This check is the check_og_tags tool in the free OnPage.dev MCP server. Connect it to Claude, ChatGPT or Cursor once, then ask in your own words.
Check how our blog post looks when it is shared on LinkedIn and X, and fix the share image if it is wrong.
check_og_tagsAnswer in the chat
Check OG tags with our API
Add Open Graph checks to your CI, dashboards or apps. Free and without a key: call the endpoint and get the score, the issues, the tags and the image details as JSON.
curl "https://onpage.dev/api/v1/og?url=https://example.com"- No key
- No sign-up or API key
- 10 requests a minute
- Per IP address
- JSON
- Cached for 5 minutes
What gets checked
- og:title, og:description, og:image, og:url, og:type and og:image:alt, and the Twitter card type for X.
- The share image itself: does it load, is it a JPG, PNG or WebP, is it at least 600 x 315 (1200 x 630 is best), is the ratio close to 1.91:1, and is it light enough to load fast.
- Relative image paths and http images on https pages, which many apps refuse to show.
Platforms cache share cards. After you fix the tags, refresh the card in the Facebook Sharing Debugger or the LinkedIn Post Inspector.
Questions
What size should an Open Graph image be?
1200 x 630 pixels, a ratio of 1.91:1, as JPG, PNG or WebP and preferably under 1 MB. Facebook ignores images under 200 x 200 and uses a small card below 600 x 315.
Is there an API?
Yes. GET https://onpage.dev/api/v1/og?url= returns the score, issues, tags and image details as JSON. It is free, needs no key, allows 10 requests a minute per IP address and caches each result for 5 minutes.
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