X (Twitter) Card Meta Tag Reference: Every Tag and Limit

Use this page as a lookup when you are writing or reviewing tags. For a guided start, use the card generator; to check an existing page, use the inspector.

Quick rules

twitter: tags use name="..."; Open Graph tags use property="...".
All URLs must be absolute. Images must be publicly reachable and served over https.
Card images: under 5 MB, JPG, PNG, WEBP or GIF (first frame), no SVG. Large image 2:1 from 300x157; summary 1:1 from 144x144; maximum 4096x4096.
Title up to 70 characters, description up to 200, image alt up to 420.
If twitter:card is missing, X may still build a summary card from og:type, og:title and og:description.

All card tags

Tag	Card types	Falls back to	Limit or format	Notes
`twitter:card`	all	`og:type (summary only)`	summary, summary_large_image, app, player	The card type. Without it, X may still build a summary card from og:type, og:title and og:description.
`twitter:site`	summary, large, app, player	—	@username	The X account of the website. Documented as required unless twitter:site:id is given.
`twitter:site:id`	summary, large, player	—	numeric user ID	Same as twitter:site but by ID, which survives handle changes.
`twitter:creator`	large (per X docs)	—	@username	The author's X account.
`twitter:creator:id`	summary, large	—	numeric user ID	The author's X account by ID.
`twitter:title`	summary, large, player	`og:title`	max 70 characters	The card headline.
`twitter:description`	summary, large, player	`og:description`	max 200 characters	Supporting text. Current X layouts often hide it on large image cards, but other apps read it.
`twitter:image`	summary, large, player	`og:image`	under 5 MB; JPG, PNG, WEBP, GIF (first frame); no SVG	Absolute URL to a publicly reachable image. 2:1 for large image, 1:1 for summary.
`twitter:image:alt`	summary, large, player	`og:image:alt`	max 420 characters	Text description of the image for people using screen readers.
`twitter:player`	player	—	HTTPS URL	The iframe page that plays the media.
`twitter:player:width / :height`	player	—	pixels	Size of the iframe.
`twitter:player:stream`	player	—	URL	Direct link to a raw video or audio stream.
`twitter:app:name:iphone / :ipad / :googleplay`	app	—	text	App name per store.
`twitter:app:id:iphone / :ipad / :googleplay`	app	—	store ID	App Store numeric ID (not the bundle ID) or the Google Play package name.
`twitter:app:url:iphone / :ipad / :googleplay`	app	—	custom scheme URL	Deep link into the app; must include :// after the scheme.

Terms used on this site

X Card (Twitter Card): The preview X shows for a posted link, built from twitter: and Open Graph meta tags in the page's HTML head.
Twitterbot: The user agent X uses to fetch shared URLs and read their card tags. It follows robots.txt.
Open Graph: A meta tag vocabulary (og:title, og:image ...) first defined by Facebook and now read by most link preview systems, including X as a fallback.
Unfurl: Slack's word for expanding a link into a preview; now used loosely for any app that turns a URL into a card.
Card cache: X's stored copy of a page's card data. X says it re-reads tags roughly every seven days; images are cached by URL.

Common questions

Which tags are required?

twitter:card in practice, plus a title and, for large image and player cards, an image (from twitter: or og: tags). X's reference also lists twitter:site as required unless twitter:site:id is given, though cards usually render without it.

Are there tags not listed here?

Older pages sometimes use twitter:image:src, twitter:domain or twitter:url. They are not in the current markup reference. twitter:label1 and twitter:data1 pairs are read by Slack on some pages but are not part of X's card markup.

Where do these limits come from?

From X's developer documentation: the Cards markup reference for tags and character limits, and the individual card type pages for image sizes. They were checked in November 2026.