Instagram post size in 2026, and the grid change most guides missed

Upload your Instagram post at 1080 pixels wide. For the height, use 1440 for a 3:4 portrait or 1350 for a 4:5 portrait. Those are the two ratios worth using in 2026, and 3:4 is the taller of the two, the tallest Instagram accepts, and the only one that fills the profile grid without losing anything off the sides. That is the whole answer, and the rest of this page is why the second half of it is newer than most guides you will find.

Every Instagram size that still matters

The change that dates most Instagram size guides

For years the advice was simple and correct: use 4:5, because 1080 x 1350 was the tallest image Instagram would accept without cropping it. Two things happened in 2025 that make that advice incomplete rather than wrong.

In January 2025, Instagram replaced the square profile grid with a 3:4 rectangle. Your profile stopped showing square thumbnails and started showing tall ones. Then in May 2025, Adam Mosseri announced that the feed itself would accept 3:4, the ratio almost every phone camera shoots at by default. His wording was that a 3:4 image would now appear, in his phrase, exactly as you shot it. Before that, 4:5 was the ceiling and anything taller was cropped or letterboxed.

So 3:4 went from being impossible to being both the tallest feed ratio and the grid ratio. That is why a guide written in 2024 and lightly refreshed since will still tell you 4:5 is the maximum. It was, and it is not.

So should you use 3:4 or 4:5?

If you are starting fresh, 3:4. It is taller in the feed, which means it occupies more of a phone screen for longer as somebody scrolls, and it survives the grid untouched. There is no case where 4:5 beats it on either count.

If you already have a library of 4:5 templates, do not rebuild them. The grid crop is about 3% a side, which is invisible on a photograph and only matters if you habitually push text or a logo right to the edge. Keep the important part of the frame away from the outer few percent and 4:5 will keep working. That is a cheaper fix than redoing a template set.

Why square posts stopped being a safe default

Square was the right answer for most of Instagram's life. It is now the weakest of the feed options, and for two separate reasons that compound. In the feed it takes the least vertical space of any portrait-capable format, so it scrolls past fastest. In the grid it loses a quarter of its width. A logo centred in a square is fine; a square laid out edge to edge is going to lose its edges.

There is still a reason to make squares, and it is a practical one rather than an Instagram one. A square crops cleanly to almost anything else, so if the same artwork has to go to a Facebook page, a Google Business post and a print flyer, starting square saves you three exports. If Instagram is the only place it goes, do not start there.

Stories and reels: 1080 x 1920, and the part you cannot use

Stories and reels are 9:16, which is 1080 x 1920. The dimension is the easy part. The part that catches people is that the interface sits on top of your image at both ends: your profile name and the close button at the top, the reply box or the caption and buttons at the bottom. Roughly the top and bottom 250 pixels of that 1920 are borrowed, and on a reel the right-hand column of buttons takes a strip as well.

Backgrounds can run to the edges, but anything a person has to read should not. How much room the interface actually takes is contested, and a reel takes noticeably more of it than a story does, so that has a page of its own rather than a number invented here. For the ideas rather than the pixels, we wrote a longer piece on story ideas for a business.

Resolution, file size and the quality question

Instagram does not display a feed image wider than 1080 pixels, and neither does Facebook, which is one reason almost every network collapses into two files. Uploading a 4000 pixel wide file does not give you a sharper post; it gives Instagram a bigger file to compress down to 1080, and the compression is not always kind. Export at 1080 wide and you have made the resizing decision yourself instead of handing it over.

• Width: 1080 pixels. More is discarded, less is upscaled and looks soft.
• Format: JPEG for photographs, PNG when there is flat colour or crisp text and you can afford the file size.
• Colour: sRGB. A file in a wider colour space can come out visibly duller after Instagram converts it.
• File size: under about 1MB is a sensible ceiling. Past that you are mostly buying heavier compression.

What happens if you get it wrong

Not much, which is worth saying plainly because size guides tend to imply catastrophe. Instagram will accept an odd size and fit it. The failure modes are ordinary: a landscape photo takes so little vertical space that it scrolls past, a square loses its edges on your profile, an upload wider than 1080 comes back a little mushier than the file you made. None of these are the reason a post did not work. If you want the reasons a post did not work, what a small business should actually post about is a better use of your afternoon than this page.

You can see the full set at whatever ratio each one came out as in the gallery, which is where every image on this page came from. If you want the posts made for you at the right size without thinking about any of this again, that is the thing we build, and what an AI social media manager actually does is the honest description of it. Getting the shape right matters more than the hour, though the hour is not nothing: the four studies of when to post on Instagram disagree by twelve hours, and where three of them overlap is worth knowing.