Link Preview Checker

Enter a URL and see the title, description and image that will appear when someone shares it - before you find out the hard way that the card is blank.

We fetch the page and read its Open Graph and Twitter card tags.

How to use the Link Preview Checker

  1. Enter the URL

    Paste the page address you are about to share. The page is fetched server-side, the same way a social platform crawler would fetch it.

  2. Review the tags that were found

    Check the Open Graph title, description and image, plus the Twitter Card type, and note anything missing or falling back.

  3. Fix and re-check

    Correct the tags, deploy, then check again. Platforms cache aggressively, so verify before the link is shared widely.

The tags that actually control a link preview

Four Open Graph tags do most of the work: og:title, og:description, og:image and og:url. Twitter reads its own twitter:card tag to decide between a small thumbnail and a large image, falling back to the Open Graph values for the rest.

Missing tags do not produce an error. The platform improvises - pulling the page title, a random paragraph, and whichever image it happens to find first, which is often a logo or a tracking pixel. The result looks broken in a way that is entirely silent from the publishing side.

Why the image is nearly always the problem

og:image must be an absolute URL. A relative path is the single most common cause of a card with no picture, because the crawler has no page context to resolve it against.

The image also has to be publicly reachable by a crawler that is not logged in, not behind a staging password, and not blocked by robots.txt. Aim for 1200 by 630 pixels; substantially smaller images get rendered as a small thumbnail or dropped, and images with a very unusual aspect ratio are cropped in ways nobody intended.

Caching, and why your fix appears not to work

Social platforms cache preview data aggressively, sometimes for days. Fixing your tags and re-sharing the same URL usually shows the old broken card, which sends people on a long hunt for a bug they have already fixed.

Each major platform provides a debugger that force-refreshes its own cache; use those after a fix. The safer habit is to get the tags right before the link is shared at all, since the first share is what populates the cache everywhere.

Frequently asked questions

Why is my link preview image not showing?
Usually a relative og:image URL where an absolute one is required, or an image that is not publicly reachable. Check that the file is not behind authentication and not blocked by robots.txt.
What size should an og:image be?
Use 1200 by 630 pixels. That ratio renders as a large card across the major platforms; much smaller images get downgraded to a thumbnail or ignored.
I fixed my tags but the old preview still shows. Why?
Platforms cache preview data for days. Use the platform own debugging tool to force a refresh - the tags on your page are already correct.
Do I need Twitter Card tags as well as Open Graph?
Only twitter:card, to choose the layout. Twitter falls back to Open Graph values for the title, description and image, so duplicating all of them is unnecessary.