Instagram image sizes by placement: feed, portrait, carousel, Reels cover, Stories and profile. Three ratios cover all of them.
The Instagram image size you want is 1080 pixels on the short edge, in one of three ratios: 4:5 for feed posts, 1:1 for square, 9:16 for Stories and Reels. Everything else on Instagram is one of those three with a different crop applied on top.
Instagram image size, by placement
Placement
Ratio
Export
Notes
Feed, portrait
4:5
1080×1350
The most screen space a single post can take
Feed, square
1:1
1080×1080
Safest for a tidy grid
Feed, landscape
1.91:1
1080×566
Smallest footprint — avoid unless the image demands it
Carousel
Same ratio for every slide
1080×1350
Mixing ratios crops the whole set to the first slide
One upload, every size exported. That is faster than remembering the table.
Why 4:5 is worth more than square
A vertical feed gives each post a fixed width and whatever height its ratio implies. A 4:5 post is therefore 25% taller than a square one at the same width — a quarter more screen, a quarter longer in view before the thumb moves on.
The trade-off is the grid: portrait posts are cropped to squares in the profile grid, so a composition with the subject at the very top or bottom looks decapitated there. Compose for 4:5 with the subject inside the central square and both views work.
Carousels: the ratio is set by the first slide
Instagram applies the first slide's ratio to the entire carousel. Add a square slide to a 4:5 carousel and it is letterboxed or cropped; the mistake is invisible in your editor and obvious in the feed.
If you are splitting a wide image across slides so it reads as one panorama, the alignment has to be exact or the seams show:
The cover appears full-height at 9:16 when the Reel is playing, and as a cropped tile in your profile grid. Those two crops share very little area, which is why so many covers have the title cut in half on the profile.
The cropper shows both crops at once so you can position the subject where it survives each. Detail: Instagram Reels cover size.
Stories: the frame is not the safe area
A Story is 9:16, but the top carries the profile row and progress bars, and the bottom carries the reply field and any stickers. Text placed in those bands is covered on some devices and clear on others.
Everything in a profile grid is square, whatever ratio it was posted at. That gives every portrait post two lives: the feed view it was composed for, and the square crop a visitor sees when they land on your profile.
Channels that care about the grid solve this in one of two ways. Either they compose 4:5 with the subject inside the central square - so the crop takes only empty space - or they accept the crop and treat the grid as a texture rather than a gallery. What does not work is centring a subject in the bottom third of a portrait image and then wondering why the profile shows a chin.
The same logic applies to Reels, which appear in the grid as a vertical tile rather than a square one, and to carousels, where only the first slide is ever shown there.
File size and format
Export as JPEG for photographs and PNG for anything with flat colour or text. Meta publishes its own creative specifications for the placements it sells advertising on (Meta Business Help), and organic posts follow the same geometry. Instagram recompresses everything, so an oversized upload is downscaled by their algorithm rather than yours — which is the usual cause of "my image looks soft on Instagram but fine on my laptop".
Instagram's ratios are the same ratios everywhere else, which is the useful thing about learning them once — 9:16 is a Story, a Reel, a TikTok and a Short. The full cross-network reference is social media image sizes.
What is the best Instagram image size?
1080×1350 at 4:5 for feed posts. It takes the most vertical space of any allowed ratio, which means more attention per post.
Why does Instagram crop my photo?
Because the ratio does not match the placement. A 16:9 image in a 4:5 slot has to lose its sides, and a carousel takes its ratio from the first slide.
Does Instagram reduce image quality?
It recompresses every upload. Exporting at the correct dimensions, already optimised, gives a better result than uploading a very large file.
What size is an Instagram profile picture?
Square, 320×320 or larger, displayed as a circle. Keep the subject centred - the corners are always cut off.
Instagram carousel size is 1080x1350 per slide, and every slide must share the first one's ratio. Here is how to split one wide image so the seams disappear.