How to preview a shared link
- Open the page in your browser and choose View Page Source (Ctrl+U, or ⌥⌘U on a Mac).
- Copy the
<head>section, or the whole source, and paste it into the box. - Read the checks: missing tags, relative URLs, repeats and lengths are listed with what to change.
- Choose or drop the share image file to see it in the cards and check its size and shape.
- Fix the tags on your page, then re-scrape it in each network's own debugger so they drop the old preview.
No HTML handy? Switch to “Fill in fields” to type a title, description, URL and image to see how a card would look.
Tags each network reads
| Network | Reads | Image |
|---|---|---|
| og:title, og:description, og:image, og:url, og:type | At least 1200 × 630 recommended; 600 × 315 for a large image; up to 8 MB | |
| X | twitter:card, then twitter: tags, falling back to og: tags | Under 5 MB; JPG, PNG, WebP or GIF; no SVG |
| og:title, og:description, og:image, og:url | 1200 × 627 at a 1.91:1 ratio; up to 5 MB | |
| WhatsApp, Slack, Discord | Open Graph tags | 1200 × 630 works well everywhere |
X documents a maximum of 70 characters for card titles and 200 for descriptions. WhatsApp, Slack and Discord don't publish a specification, so their cards here follow the Open Graph tags as they're commonly displayed.
Common reasons a preview looks wrong
- Relative image URL.
/images/share.jpgworks in your page but not for a network's crawler. Use the full https:// address. - An old cached preview. Networks cache cards, and Facebook caches images by URL. Re-scrape the page, and give a changed image a new file name.
- Repeated tags. Two og:title tags, often from a theme and a plugin, mean the first one wins.
- Missing twitter:card. Without it X may show only a small card, or none.
- Image too small or the wrong shape. Large cards are about 1.91:1; anything else is cropped.
Sources
Each link was last checked on .
- The Open Graph protocol, The Open Graph protocol: the og:title, og:type, og:image and og:url properties, image structured properties, and that the first of repeated tags wins.
- Cards markup tag reference, X Developer Platform (archived copy of 1 February 2026; the live page now redirects): twitter:card types, title up to 70 and description up to 200 characters, images under 5 MB, and Open Graph fallbacks.
- A Guide to Sharing for Webmasters, Meta for Developers: the og: tags Facebook reads for link previews, and that shared images are cached by URL.
- Images in link shares, Meta for Developers: images of at least 1200 × 630 pixels, close to 1.91:1, and no larger than 8 MB.
- Make your website shareable on LinkedIn, LinkedIn Help: og:title, og:image, og:description and og:url, and images of 1200 × 627 pixels up to 5 MB.
Common uses
- Before sharing a launch post. Paste the page's head to check every network will show the right title, description and image before the link goes out to thousands of people.
- Debugging a blank WhatsApp preview. See which tags are missing or relative, such as an og:image without https and the domain, which is a common reason a link shows no picture.
- Checking a new share image. Choose the image file to see how it's cropped in large and small cards and whether it meets the 1200 × 630 recommendation and file-size limits.