How to validate your Twitter card
- 1
Paste your URL
Any public page. We fetch it and read every
twitter:andog:tag in its head. - 2
See the X card
The result opens on the X preview:
summary_large_imageorsummary, with the image, title and domain X will use. - 3
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, X asks for an image close to 2:1, at least 300 × 157 and at most 4096 × 4096 pixels, under 5 MB, as JPG, PNG, WebP or GIF (an animated GIF shows only its first frame).
The standard 1200 × 630 Open Graph image works: at 1.91:1 it loses only a sliver at the top and bottom when X crops it to 2:1, so keep text away from those edges.
Need an image at the right size? Create one with the free OG image generator and download a ready 1200 × 630 PNG.