Reference · Image specs
Social media image sizes, from the platforms themselves
What each platform actually documents for post images: aspect ratios, file-size caps, and the honest gaps where a platform documents nothing at all. Every value links to the platform's own page and the date it was read.
Most "social media image sizes" charts on the internet are the same invented table wearing different fonts. The truth is more useful and less tidy: the platforms mostly document ASPECT RATIOS, not pixel dimensions. Instagram's help pages talk about ratios; Facebook's organic docs say nothing about a fixed size at all; and a platform that documents no organic size is shown here as "not officially documented" rather than given a made-up number.
The practical rule that survives the honesty filter: build your image once at a generous square or portrait size, keep the aspect ratio the platform asks for, and let the platform resize. The rows below are the documented numbers that actually exist, each read off the platform's own page on 6 August 2026.
What each platform documents
Image rows only, from the same sourced reference the full spec page uses. A gap is a gap, not a guess.
| Spec | What the platform documents |
|---|---|
| recommended image aspect ratio | not officially documented (organic)Aspect-ratio guidance exists only in Meta Ads Manager docs; no organic aspect ratio stated on fetched pages.Source: Facebook docs, checked 2026-08-06 |
| image max file size | 10MB (PNG recommended <=1MB to avoid pixelation); formats .jpeg, .bmp, .png, .gif, .tiffExact text: 'Files can not exceed 10MB. For .png files, we recommend not exceeding 1MB or the image may appear pixelated.'Source: Facebook docs, checked 2026-08-06 |
| Spec | What the platform documents |
|---|---|
| recommended image aspect ratio + max file size | Aspect ratio must be within 4:5 to 1.91:1; JPEG only; 8MB max; width 320-1440pxSource: Instagram docs, checked 2026-08-06 |
| Spec | What the platform documents |
|---|---|
| recommended image aspect ratio + max file size | Aspect ratio 3:1 to 4:5 (width:height); 5MB max per upload; min 552x276px, recommended 1080px wide; up to 20 photos per multi-photo postSource: LinkedIn docs, checked 2026-08-06 |
X
| Spec | What the platform documents |
|---|---|
| recommended image aspect ratio + max file size | Photos up to 5MB; animated GIFs up to 5MB mobile / 15MB web; GIF, JPEG, PNG only; 1-4 photos per post. Aspect ratio: not officially documented for photosSource: X docs, checked 2026-08-06 |
TikTok
| Spec | What the platform documents |
|---|---|
| recommended image aspect ratio + max file size (photo posts) | Max 20MB per image; WebP/JPEG; picture size maximum 1080p. Aspect ratio: not officially documentedSource: TikTok docs, checked 2026-08-06 |
YouTube (Shorts)
| Spec | What the platform documents |
|---|---|
| recommended image aspect ratio + max file size (thumbnail) | Thumbnail: 16:9 recommended (Shorts thumbnail 9:16, 2160x3840); resolution 3840x2160 (min width 640px); 2MB mobile / 50MB desktop; JPG, GIF, PNGYouTube has no organic feed-image concept; thumbnail is the image spec.Source: YouTube (Shorts) docs, checked 2026-08-06 |
| Spec | What the platform documents |
|---|---|
| recommended image aspect ratio + max file size | Max file size: 20MB (web) / 1GB recommended (Android and iOS); file types .BMP, .JPEG, .PNG, .TIFF, .WEBP. Aspect ratio: not officially documented for organic image PinsThe 2:3 (1000x1500px) recommendation, 20MB desktop / 32MB in-app caps and PNG/JPEG-only list are Pinterest's ad-format specs, excluded per the organic-only rule. The organic page gives image Pins safe zones rather than an aspect ratio.Source: Pinterest docs, checked 2026-08-06 |
Google Business Profile
| Spec | What the platform documents |
|---|---|
| recommended image aspect ratio + max file size | JPG or PNG; between 10KB and 5MB; recommended resolution 720x720px; minimum 250x250px. Aspect ratio: not stated beyond square recommendationSource: Google Business Profile docs, checked 2026-08-06 |
Mailchimp (email)
| Spec | What the platform documents |
|---|---|
| recommended image aspect ratio + max file size | 'We recommend a maximum file size of 1MB for images'; PNG, JPG, or GIF; new builder image width 660-1320px (legacy 600-1200px). Content studio upload limits: images up to 1MB each, other files up to 10MB each. Aspect ratio: not officially documentedContent studio limits from https://mailchimp.com/help/use-the-content-studio/ (also checked 2026-08-06).Source: Mailchimp (email) docs, checked 2026-08-06 |
How to pick a size without the charts
Aspect ratio first, pixels second
The ratio is what the platform states and what its feeds crop to. If you get the ratio right at a decent resolution, the platform's resize does the rest. Fixed pixel charts are the giveaway that a table was invented.
One master image, exported per ratio
Design one square master with safe margins, then export the portrait and landscape crops from it. The safe-margin habit matters more than any single dimension, because feeds crop edges differently.
Keep the file under the documented cap
Where a platform states a max file size, stay under it. Where it does not, the sane default is a few megabytes: large enough to stay sharp, small enough to upload everywhere.
Questions people ask about image sizes
What size should my images be for every platform at once?
There is no one pixel size, and any chart that claims one is inventing. What the platforms actually document is aspect ratios. A square 1080x1080 master with safe margins, exported to portrait and landscape as needed, covers the documented organic surface. The rows above are the documented numbers.
Why do most platforms not document pixel dimensions?
Because their feeds are responsive: the same post renders at different sizes on different screens. What stays constant is the aspect ratio and the file-size cap, so that is what the platforms publish. This page records a gap as a gap instead of filling it from a third-party chart.
Do Stories and feed posts use different sizes?
Where a platform documents a separate ratio for Stories or thumbnails, it is a separate row above. Where it does not, the feed ratio is the only documented number, and the page says so rather than guessing a Story size.
How often do these numbers change?
Rarely, but when a platform updates its docs, the spec reference this page is built from gets re-checked and its change log records the move. Every row here carries the URL it was read from and the date it was checked, so staleness is visible instead of hidden.
Does SpeedRun Social generate images at these sizes?
SpeedRun generates each post's image at the aspect ratio its destination platform expects, from the business's own brand kit, as part of the weekly campaign. The free plan includes one campaign a week with no card. The numbers on this page are the sourced reference the product builds against.
Have your images made at the right ratio
SpeedRun generates each post's image at its platform's aspect ratio from your own brand kit. One campaign a week is free, no card required.