Every “recommended OG image size” article confidently states the same number - usually 1200x630 - and stops there. The reality is messier: each platform crops, resizes, and falls back differently. Here’s what actually works in 2026.

The minimum that satisfies everyone

If you can only ship one image, ship 1200x630 as JPEG or PNG, under 8 MB. It clears Facebook’s strict guidance (>=1200x630), LinkedIn’s (1200x627), Twitter’s summary_large_image (>=1200x675 strict, >=600x335 fallback), Discord’s embed, and Slack’s unfurl.

It will not satisfy twitter:card=summary, which expects a 1:1 image. That one has its own column below.

Per-platform breakdown

Facebook + LinkedIn

Aspect ratio 1.91:1. Recommended 1200x630, minimum 600x315. LinkedIn officially asks for 1200x627 but is forgiving. If og:image:width and og:image:height are set, Facebook trusts them and skips a refetch.

After

og:image - absolute URL, must serve over HTTPS, must be reachable to anonymous fetch.
og:image:width + og:image:height - strongly recommended.
og:image:alt - accessibility, not display.

Twitter summary_large_image

Aspect ratio 2:1. Recommended 1200x675. Minimum 600x335. Strict max file size 5 MB. Image is cropped center if uploaded outside ratio.

After

twitter:card = summary_large_image
twitter:image - absolute URL.
twitter:image:alt - accessibility.

Twitter summary (1:1)

Aspect ratio 1:1. Recommended 400x400, minimum 144x144. Used when twitter:card=summary. Common for podcasts, profiles, single-author posts.

After

twitter:card = summary
twitter:image - square. Don’t reuse the 1200x630.

What Discord and Slack do

Both follow Open Graph faithfully. Discord renders the full og:image with embed treatment (colored left bar, title, description, image). Slack’s unfurl shows the image below the title + description. Both respect og:image:width/og:image:height for layout reservation.

What iMessage does

Apple’s Smart Links read og:image, og:title, og:description. Image renders at the top of the chat bubble. If image is square or vertical, iMessage scales to a square - your wide 1200x630 looks fine.

What Metaspry checks

og:image-dimensions (async rule) - loads the image in the browser, reads naturalWidth / naturalHeight. >=1200x630 = pass. >=600x315 = warn (“recommend >=1200x630”). Below = fail.

og:image-absolute - verifies the URL is http:// or https:// (not relative, not data: for OG).

The rest you see in the Previews tab - each platform card uses the actual image; what you see is what crawlers see.

The minimum-effort plan

Ship one 1200x630 PNG for og:image.
Ship a 1200x675 version for twitter:image when you remember.
Set og:image:width + og:image:height to the exact pixels.
Set og:image:alt for accessibility.

That’s it. Skip the rest until you have a reason to care.