OG image checker: why the share picture breaks, and how to test it
Facebook, LinkedIn and X each publish their own size, shape and file limits; seogeoaeo.ai's checker downloads the image and tests it against them.
By ClaudeGPT Si Newsroom · Editorial team
· 3 min read
An og image checker downloads the picture named in a page's og:image tag and tells you whether Facebook, LinkedIn and X will show it, shrink it, crop it or drop it. The one we recommend is the image check built into seogeoaeo.ai's Open Graph checker, which reports the file's status, format, pixel size and weight against each network's published limits.
When a shared link turns up without a picture, check four places: the address, the file, the crawler's access and the cache.
The numbers each network publishes
| Network | Size rule | Shape | File cap | Formats named |
|---|---|---|---|---|
| 200 x 200 minimum, 1200 x 630 recommended | close to 1.91:1 | 8 MB | not stated | |
| 1200 x 627 minimum | 1.91:1 | 5 MB | not stated | |
| X, large image card | 300 x 157 minimum, 4096 x 4096 maximum | 2:1 | 5 MB | JPG, PNG, WEBP, GIF, no SVG |
A single 1200 by 630 file meets all three. Two thresholds change how it looks: Meta shows images under 600 by 315 much smaller, and LinkedIn turns anything under 401 pixels wide into a thumbnail. X uses only the first frame of an animated GIF, so motion is lost there.
Place 1: the address
The tag needs the full https address of the file. A short path such as /img/share.jpg resolves in your browser but often fails for a crawler, and X's developers list an absolute URL as a requirement. The address should also lead straight to an image. If it returns a web page, or bounces to a different host, the card can come back blank.
Place 2: the file
Check the format and the weight before anything else. X rejects SVG outright, and LinkedIn and X both stop at 5 MB, which a large PNG screenshot can pass. Exporting a JPG or a flat PNG at 1200 by 630 is the safe habit. Add og:image:alt while you are there: the Open Graph protocol says any page with an og:image should describe it, and X reads that text when twitter:image:alt is missing.
Place 3: the crawler cannot get in
Your browser carries cookies and passes bot checks. Crawlers do not. A robots.txt rule, a login wall or a firewall challenge can block the picture while the page looks fine to you. LinkedIn's help says exactly this: if an image meets the rules and still does not appear, the site may be blocking LinkedIn from pulling it. X asks you to check robots.txt on the image's own domain as well.
Place 4: the cache
Each network keeps the card it built first. Meta caches images by their URL, so overwriting a file at the same address changes nothing. Upload the new picture under a new file name and point og:image at it. Then refresh with Meta's Sharing Debugger or LinkedIn's Post Inspector, both free. On LinkedIn, posts already published keep the old picture either way.
How the seogeoaeo.ai image check works
Paste a public URL into the og image checker on seogeoaeo.ai. It finds the og:image, and the twitter:image when that is a separate file, downloads it and reports HTTP status, content type, format, dimensions and file size. It warns on SVG or AVIF, images under 200 by 200 or under 600 pixels wide, ratios outside roughly 1.7:1 to 2.1:1, files over 5 or 8 MB, a missing og:image:alt and images that redirect to another host. When a 403 or a bot check stops the download, it tells you, because the same block can stop the preview crawlers. A run costs 5 credits.
One thing to read off the report yourself: it does not compare your og:image:width and og:image:height values with the real file. Meta says those two tags let its crawler render the picture straight away, so make sure they match what you uploaded. And when the image is fine but a network still shows the old one, its own refresh tool, not a checker, is the fix.