The twitter:card tag

The only required Twitter-specific tag. It controls which card layout Twitter uses:

• summary: small square thumbnail with title and description
• summary_large_image: large image above the title (most common)
• player: embedded media player
• app: app install card

Without it, Twitter may fall back to a basic summary or show nothing at all. This is the most common cause of missing cards.

<meta name="twitter:card" content="summary_large_image">

Tag fallback behavior

Twitter checks for twitter:* tags first, then falls back to Open Graph:

If you already have OG tags, you typically only need to add twitter:card.

The twitter:site tag

The @username of the website, displayed in the card footer.

<meta name="twitter:site" content="@yoursite">

The twitter:creator tag

The @username of the content author, distinct from the site account. Useful for multi-author publications.

<meta name="twitter:creator" content="@authorname">

Minimal setup

If you already have Open Graph tags, this is all you need:

<meta name="twitter:card" content="summary_large_image">
<meta name="twitter:site" content="@yoursite">

Twitter picks up og:title, og:description, and og:image for the rest.