Twitter Card Checker
See what a page will look like shared on X, including which values come from Open Graph.
About this tool
Reads a page's `twitter:` tags, works out what will actually be displayed, and shows where each value came from.
That last part is what most checkers get wrong. **X falls back to Open Graph for everything except the card type itself.** A page with a complete set of `og:` tags plus one `twitter:card` line has a working card, and a report listing five missing `twitter:` tags on that page is five pieces of work that would change nothing at all.
What genuinely has no fallback is `twitter:card`. Without it the link is posted as a bare URL with no preview, which is the difference between a post people click and a post they scroll past.
Image dimensions are read from the markup, not measured — this tool does not download the image.
Common questions
Do I need twitter: tags if I already have Open Graph?
Only twitter:card. X reads og:title, og:description and og:image directly when the twitter: equivalents are absent. Adding duplicates of tags that already fall back correctly is work with no effect.
Which card type should I use?
summary_large_image for articles and anything with a good image — it takes far more space in the timeline. summary for pages whose image is a logo, where a full-width version looks stretched.
Why does my card not update after I changed the tags?
X caches card data for around a week. Nothing you do to the page clears it sooner; the usual workaround is sharing the URL with a query string appended, which counts as a different URL.
What image size should I use?
At least 1200 by 628 for a large image card, under 5MB, and 2:1 or wider. Anything much smaller is either upscaled or falls back to the small card format.