/tools/twitter-card-validator · free, no sign-up
Twitter card validator
X retired its own Card Validator. Paste a URL and see the card X builds from it, a large image or a small thumbnail, with what to fix: twitter:card, the og:image size and format, the title and description. LinkedIn, Slack and Discord come with it.
We fetch the page once, with its share image, favicon, robots.txt and llms.txt. We don’t save the report.
The tags a good share card needs
| tag | what to put in it |
|---|---|
| og:title | The product name and what it does, under about 60 characters. |
| og:description | One or two sentences, under about 160 characters. |
| og:image | An absolute https:// URL to a 1200×630 PNG or JPEG under 5 MB. |
| og:image:alt | What the image shows, for screen readers. |
| og:site_name | Your product or site name; Slack and Discord show it above the title. |
| twitter:card | summary_large_image, so X shows the image full width. |
<meta property="og:title" content="Acme — invoices that chase themselves">
<meta property="og:description" content="Acme sends your invoices and follows up until they're paid.">
<meta property="og:image" content="https://acme.com/og.png">
<meta property="og:image:alt" content="Acme's invoice list with three paid invoices">
<meta property="og:site_name" content="Acme">
<meta name="twitter:card" content="summary_large_image">
Questions
What’s the difference between summary and summary_large_image?
“summary” shows a small square thumbnail next to the title and description; X asks for a 1:1 image of at least 144×144. “summary_large_image” shows the image full width above the text, at about 2:1, at least 300×157; 1200×630 works on X and every other platform at once.
Do I need twitter: tags if I already have Open Graph tags?
Only twitter:card. When a twitter: tag is missing, X reads og:title, og:description and og:image instead, so a page with good Open Graph tags needs just <meta name="twitter:card" content="summary_large_image"> to get a large card on X.
Why does X show a small card or no image?
X needs <meta name="twitter:card" content="summary_large_image"> for a full-width image; "summary" gives a small square thumbnail. X reads og:title, og:description and og:image when the twitter: tags are missing. X retired its own Card Validator, so a checker like this one is the way to preview the card before you post.
I changed my og:image. Why do previews still show the old one?
Platforms cache previews. Give the new image a new URL (a version in the file name or query string), then use LinkedIn’s Post Inspector or Facebook’s Sharing Debugger to refresh their copy; Slack and Discord pick it up after their cache expires.
Do you store the pages I check?
No. We fetch the page, its share image, favicon, robots.txt and llms.txt once and show you the report; we don’t save it.
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The same check, leading with something else: OG image checker, Meta title and description checker, llms.txt checker. More in free tools.