How to validate your Twitter card
- 01
Paste your URL
Any public page. We fetch it and read every twitter: and og: tag in its head.
- 02
See the X card
The result opens on the X preview: summary_large_image or summary, with the image, title and domain X will use.
- 03
Fix what's flagged
Each problem links to a plain-English fix, with the exact tag to add. Re-run the check to confirm it is live.
Why X's own Card Validator no longer helps
In 2022 X removed the preview from its Card Validator at cards-dev.twitter.com. The page still loads, but it no longer shows the card your link will produce. X's suggestion is to start composing a post and look at the preview there.
That works for a quick look, but it tells you nothing about why a card is broken. This validator shows the same card without posting and lists each tag it read, so you can see which one is missing or wrong.
The tags X reads, and what it falls back to
X reads Open Graph tags when a Twitter-specific tag is missing. twitter:card is the exception: it has no fallback, and without it your link can post as a bare URL.
| Tag | Falls back to | Notes |
|---|---|---|
| twitter:card | None | Picks the layout. Use summary_large_image for a full-width image. |
| twitter:title | og:title | Only set it when X should show different copy. |
| twitter:description | og:description | Only set it when X should show different copy. |
| twitter:image | og:image | 1200 × 630 for summary_large_image; under 5 MB. |
| twitter:site | None | The publisher's @handle. Attribution only; no effect on layout. |
<meta name="twitter:card" content="summary_large_image" />
<meta name="twitter:site" content="@yourhandle" />
<meta property="og:title" content="Your page title" />
<meta property="og:description" content="One or two sentences." />
<meta property="og:image" content="https://example.com/og.png" />Twitter card image size
For summary_large_image, use 1200 × 630 pixels at a 1.91:1 ratio, the same size as your Open Graph image. Below about 300 × 157 pixels X quietly switches to the small summary card. Keep the file under 5 MB.
Need an image at the right size? Start from a free template and download a ready 1200 × 630 PNG.
Fix a broken X card
Frequently asked questions
What is a Twitter card validator?
A Twitter card validator fetches a URL, reads its Twitter Card and Open Graph tags, and shows the card X will build from them: the layout, image, title, description and domain. It flags missing or broken tags before you post the link.
What happened to X's own Card Validator?
In 2022 X removed the preview from its Card Validator at cards-dev.twitter.com. The page still exists, but it no longer shows you the card. X now suggests composing a post to see the preview, which means publishing to test. This validator shows the preview without posting anything.
Why is my Twitter card not showing an image?
The usual causes are a missing twitter:card tag, an og:image that is a relative URL or returns an error, an image under 300 × 157 pixels, or a file over 5 MB. Run the URL through the validator; each of these is flagged with a fix.
Why does X show a small thumbnail instead of a large image?
Either twitter:card is set to summary rather than summary_large_image, or the image is too small and X has silently downgraded the card. Set summary_large_image and use a 1200 × 630 image.
Do I need twitter:image if I already have og:image?
No. X falls back to og:image, og:title and og:description. twitter:card is the one tag with no Open Graph fallback, so it is the one to add.
I fixed my tags. Why does X still show the old card?
X caches card data per URL, and posts that already exist keep their old card. Confirm the new tags are live here, then share the link again. Adding a query string such as ?v=2 gives X a fresh URL to fetch.
Is this Twitter card validator free?
Yes. There is no sign-up and no limit on the URLs you check. The same scan also previews Facebook, LinkedIn, WhatsApp and Discord.