Twitter card validator and Open Graph checker

X retired its own card validator, so here's a free one. Enter a URL to preview how the link will look on X, Facebook and LinkedIn, and find missing or broken og: and twitter: tags.

Free, no signup. Checks one page.

What this tool checks

  • Previews of the link card on X, Facebook and LinkedIn
  • twitter:card type, and what X falls back to when twitter: tags are missing
  • The basic Open Graph tags: og:title, og:type, og:image, og:url and og:description
  • Downloads the share image: does it load, is it a supported format, how big is it
  • Image size rules: 1200×630 recommended, 200×200 minimum, 5 MB limit on X
  • Relative image URLs, conflicting duplicate tags and titles that get cut off

How X, Facebook and LinkedIn build a link preview

When someone shares a link, the platform fetches the page and reads its Open Graph tags (og:title, og:description, og:image) to build the card. X reads its own twitter: tags first and falls back to Open Graph for anything missing, so a page with good og: tags only needs one extra line: twitter:card, which picks the layout.

The image does most of the work. Use 1200×630 pixels (about 1.91:1) as a JPG or PNG under 1 MB, with an absolute URL. SVGs aren't shown, images under 200×200 are ignored by Facebook, and anything over 5 MB is skipped by X.

Platforms cache previews. After fixing your tags, a link that was already shared can keep the old card for a while. Facebook's Sharing Debugger and LinkedIn's Post Inspector can force a refresh; X refreshes on its own within about a week.

Frequently asked questions

Is there still a Twitter card validator?

X removed the preview from its own Card Validator in 2022. This tool does the same job: it reads the page's twitter: and Open Graph tags, checks the image and shows a preview of the card.

Which twitter:card type should I use?

summary_large_image for most pages: it shows a full-width image above the title. summary shows a small square thumbnail beside the text, which suits profile pages and logos. app and player are for app installs and video.

Does X use Open Graph tags?

Yes. If twitter:title, twitter:description or twitter:image are missing, X uses og:title, og:description and og:image. You still need twitter:card to choose the layout.

What size should an og:image be?

1200×630 pixels works everywhere. The minimum is 200×200 on Facebook and 300×157 for X's large card. Keep the file under 1 MB and important text away from the edges, since some platforms crop to a square.

Why is my link preview not showing the image?

Common causes: the og:image URL is relative or broken, the image is an SVG or too small, the server blocks bots, or the platform cached an old version. Run the URL above to check the first four, then refresh the cache with Facebook's Sharing Debugger.

Why does my link preview show the wrong title?

Platforms use og:title (or twitter:title on X) before the page's <title>. If there are two og:title tags, often one from the theme and one from an SEO plugin, they usually take the first. The checker lists every tag it found.

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