2026-10-10

Facebook and LinkedIn's actual og:image size rules — and why your link preview looks wrong

Paste a link into a Facebook post, a LinkedIn update, or a Messenger chat, and the preview card that pops up is built entirely from a handful of <meta> tags on the page you linked to — not from anything clever the platform does with your text. The one that decides the picture is og:image, and both Facebook and LinkedIn publish their own exact pixel rules for it. When a shared link shows a blank box, an oddly cropped sliver, or a tiny thumbnail instead of the big card, the image almost always just doesn't clear the numbers either platform's own documentation sets — not a sharing bug.

Facebook's own numbers, word for word

Facebook's Sharing documentation for images states the floor plainly: “the minimum allowed image dimension is 200 x 200 pixels.” Below that, Facebook won't use the image at all. For the large, full-width preview card — the one most people actually want — the same page sets a higher bar: “use images that are at least 1200 x 630 pixels for the best display on high resolution devices,” and separately, “at the minimum, you should use images that are 600 x 315 pixels to display link page posts with larger images.” Anything smaller than that 600×315 floor still shows, but only as a small thumbnail next to the link text, not the large card. File size has its own hard limit: “the size of the image file must not exceed 8 MB.” Facebook also recommends keeping the image close to a 1.91:1 width-to-height ratio so the News Feed crop doesn't cut pieces off it, and adding og:image:width and og:image:height tags so its crawler can lay the card out without downloading the image first.

LinkedIn's floor is higher than it looks

LinkedIn's own help page for making a website shareable sets a stricter minimum than Facebook's: a website-share image needs to be at least 1200 (width) × 627 (height) pixels, at a recommended 1.91:1 aspect ratio, under a 5 MB file cap. The same page adds a detail most guides skip — images narrower than 401 pixels render as a small thumbnail instead of the large card, the same “falls back to tiny” behavior Facebook has at a different pixel count. The practical trap: an image that already clears Facebook's 200×200 floor, or even its 600×315 large-card threshold, can still be too small for LinkedIn's harder 1200×627 line. A photo that looks fine shared on Facebook can quietly become a thumbnail-only card the moment the same link is pasted into a LinkedIn post.

Why the image sometimes doesn't update even after you fix it

Facebook's own documentation notes that it caches an og:image by the page's URL — re-uploading a differently sized image to the exact same image URL doesn't make the old preview disappear on its own. Facebook's Sharing Debugger tool lets you force a re-scrape of a specific page URL so the new image (and its new dimensions) get picked up; changing the image file's own URL has the same effect, since there's nothing left to have cached. This is a separate step from fixing the image itself, and it's the part people usually miss after they've already corrected the size.

Fixing the image with nearIMG

• Resize using the OpenGraph preset, not a manual guess. nearIMG's Resize for Social tool ships a “Web / Blog” preset group that includes “OpenGraph (link preview)” at an exact 1200×630 — Facebook's own recommended size, and tall enough to clear LinkedIn's 1200×627 floor by 3 pixels. Picking it from the preset dropdown sets both dimensions at once; no typing pixel numbers by hand.
• Crop first if the source isn't already close to 1.91:1. A square product photo or a tall phone screenshot is far from that ratio, and nearIMG's Crop tool doesn't carry an exact 1.91:1 preset among its 1:1, 4:3, 16:9, and 3:4 options — drag the crop box by eye to roughly that shape (noticeably wider than tall) before the exact-pixel Resize step finishes the job, so the platform's own feed layout isn't left to guess what to trim.
• Convert to JPG for the smallest file. A 1200×630px JPG sits nowhere near Facebook's 8 MB cap or LinkedIn's 5 MB cap even at a high quality setting, so there's no reason to push the compression slider hard enough to visibly soften the image.

What this doesn't do

• nearIMG doesn't edit your page's <meta property="og:image"> tag. That's a line of HTML (or a CMS field) pointing at wherever you host the image — a separate, code-level change from producing the image file itself.
• nearIMG can't force Facebook or LinkedIn to re-scrape a cached preview. That's what Facebook's own Sharing Debugger (and LinkedIn's Post Inspector) are for — an image tool has no way to reach into either platform's cache.
• This piece only quotes numbers Facebook and LinkedIn publish themselves. X (Twitter), Slack, Discord, and iMessage previews also read an og:image tag in practice, but neither currently publishes the same kind of specific, citable pixel/file-size page the way Facebook and LinkedIn do, so no numbers for them are claimed here.

The short version

Facebook's own Sharing documentation wants an og:image at least 600×315 — recommending 1200×630 — under 8 MB, near a 1.91:1 ratio, or it falls back to a small thumbnail below 200×200. LinkedIn's own help page sets a harder floor of 1200×627, under 5 MB, at the same 1.91:1 ratio, or it does the same thumbnail fallback below 401px wide. nearIMG's OpenGraph (link preview) preset under Resize for Social sets the exact 1200×630 pixels that clears both at once, entirely in the browser — the remaining step, fixing the og:image tag itself and re-scraping the cached preview, happens outside any image tool.