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Open Graph & Twitter Card Checker

Enter a URL or paste HTML. We read the og: and twitter: tags, load the og:image and check it against Facebook and X limits, then show how the card will look.

OG Image Requirements, Facebook and X

RequirementFacebookX (large image card)
Minimum size200 x 200 (smaller is not shown)300 x 157 for a large image card
Large previewAt least 600 x 3152:1 aspect ratio
Recommended1200 x 630 or larger2:1, for example 1200 x 600
Maximum sizeNot documented4096 x 4096
File weight8 MB at mostUnder 5 MB
FormatsNot listedJPG, PNG, WEBP, GIF (first frame). No SVG

Facebook figures from its Sharing for Webmasters documentation, X figures from its developer documentation for the summary card with large image. We could not verify LinkedIn's current limits from LinkedIn itself, so they are not listed rather than guessed.

The Tags Every Shareable Page Needs

Six Open Graph tags and one Twitter tag cover Facebook, LinkedIn, X, Slack, Discord, Teams and most other places a link gets pasted. Image URLs must be absolute, starting with https://.

<meta property="og:title" content="Summer sale: 30% off everything">
<meta property="og:description" content="Until Sunday, on every item in the shop.">
<meta property="og:image" content="https://example.com/og/summer-sale.png">
<meta property="og:url" content="https://example.com/summer-sale">
<meta property="og:type" content="website">
<meta property="og:site_name" content="Example Shop">
<meta name="twitter:card" content="summary_large_image">

og:title and og:description can differ from the page's <title> and meta description: those are written for search results, these for a feed. To check the search side, use the meta tag checker.

Why the Twitter Card Validator Is Not Enough Any More

X's Card Validator stopped showing card previews in 2022. The tags still matter: X reads twitter:card to pick the layout and falls back to your Open Graph tags for the title, description and image. What changed is that you can no longer see the result before posting.

This checker fills that gap without posting anything: it shows the large image card or the summary card depending on your twitter:card value, and checks the image against X's limits (2:1, at least 300 x 157, under 5 MB, no SVG). The preview is an approximation of X's layout, not a screenshot of it.

Frequently Asked Questions

What size should an Open Graph image be?
1200 x 630 pixels is the safe choice: it is Facebook's recommended size and close to the 2:1 ratio X uses for large image cards. Facebook will not show an image smaller than 200 x 200, shows a small thumbnail below 600 x 315, and refuses files over 8 MB. X refuses card images of 5 MB or more. This checker loads your image and tells you which of those it meets.
Is there still a Twitter Card Validator?
X's own Card Validator stopped rendering card previews in 2022, and X points people to the post composer to see a card. This page shows an approximate X preview from your tags, checks that twitter:card is set, and checks the image against X's documented limits, which is what the validator used to be for.
Do I need Twitter Card tags if I already have Open Graph tags?
Mostly not. X falls back to og:title, og:description and og:image when the twitter: versions are missing. Add twitter:card to choose the layout: summary_large_image for a wide image, summary for a small square one. Add the other twitter: tags only if you want X to show something different from other platforms.
I fixed my tags but the old preview still shows. Why?
Platforms cache a link the first time they see it. Facebook's Sharing Debugger (developers.facebook.com/tools/debug) has a Scrape Again button that refetches the page, and LinkedIn's Post Inspector (linkedin.com/post-inspector) does the same for LinkedIn. Messaging apps refresh on their own schedule.
Can I check a page on localhost or behind a login?
Yes. Choose Paste HTML and paste the page's source, or just its <head>. Platforms cannot reach such a page at all, so this is the only way to see the card before you publish. Add the page address if your og:image URL is relative, so the image can be loaded and measured.
Why does my og:image not show?
The usual causes, all reported by this checker: the URL is relative instead of absolute, the URL returns an error or an HTML page instead of an image, the file is an SVG, the image is smaller than 200 x 200, or the file is heavier than the platform accepts.
What is the difference between Open Graph and Schema.org markup?
Open Graph controls the card shown when a link is shared on social networks and in chat apps. Schema.org markup, usually JSON-LD, helps search engines understand the page and can earn rich results in Google. They do not conflict, and most sites need both.

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