Resize Images for Instagram
Instagram runs every upload through its own scale-and-recompress pipeline, so the goal is not avoiding that pass — nobody can — but giving it nothing to do except compression. The table below lists the pixel sizes that survive it best, four of which are one-click presets on this tool's Social Media tab. Arrive at these exact dimensions and the crop and the resample both happened on your screen, under your eyes, instead of on a server in a data centre.
Instagram sizes at a glance
| Where it goes | Size in pixels | Shape |
|---|---|---|
| Feed post — square | 1080 x 1080 | 1:1 |
| Feed post — portrait | 1080 x 1350 | 4:5 |
| Feed post — landscape | 1080 x 566 | 1.91:1 |
| Story and Reel | 1080 x 1920 | 9:16 |
| Profile picture | 320 x 320 | 1:1, shown as a circle |
What Instagram's servers do with your upload
Anything wider than 1080 pixels is scaled down on Instagram's side, and everything — whatever its size — is re-encoded with compression tuned for their bandwidth bill rather than for your photo. There is no setting, account type or file trick that opts out of it.
What you control is the input to that machine. Send a 4000-pixel original and their servers choose the resampling, the crop and the final look, sight unseen. Send exactly 1080 pixels and their encoder merely recompresses a result you have already inspected — the sharpening, the framing and the detail were all decided by you. That is the entire argument for resizing before posting: not better maths, but the ability to see the outcome first. File size, by contrast, is nearly irrelevant; their re-encode discards your careful kilobytes either way.
Four shapes, four different jobs
The portrait post at 4:5 takes the most vertical room a feed image can occupy, which is why it has become the default for photography accounts; the 1.91:1 landscape is the opposite — the smallest footprint, the easiest to scroll past, best kept for images that are genuinely wide. The square sits between them and forgives almost any subject.
Stories and Reels fill the phone screen at 9:16, but the app lays its own interface over both ends — camera and profile controls at the top, reply and action buttons along the bottom — so keep faces and text in the middle band. The profile picture uploads at 320 x 320 and is displayed as a small circle; check that your subject still reads with the corners gone before committing to it.
Getting an off-shape photo into a preset
The preset buttons pair with the Fill & Crop fit mode: your photo is scaled until it covers the target shape and the overflow is trimmed evenly from both sides. The centre survives; the edges are sacrificed. When the subject is not centred, do the framing yourself in the image cropper first, then bring the already-shaped picture here for the final pixel dimensions.
One deliberate quirk is worth knowing: choosing a preset overrides the do-not-enlarge guard. A preset that only half-applied would produce dimensions matching no Instagram format at all, so the preset wins even when your source is smaller than the target — at the cost of some sharpness, a trade the tool chooses to make visible on screen rather than hiding from you.
Frequently Asked Questions
Which size should I use for a feed photo?
The 4:5 portrait at 1080 x 1350 occupies the most screen while someone scrolls, which is why most photo-first accounts standardise on it. The Portrait Post preset applies it in one click.
What are the Story and Reel dimensions?
1080 x 1920, a 9:16 shape shared by both. Compose for the middle of the frame, because the app draws its interface over the top and bottom edges.
Why do my photos look worse on Instagram than on my phone?
Their servers re-encode every upload with aggressive compression, and nothing exempts you from it. Arriving at exactly 1080 pixels wide with high quality gives their encoder the least work to do, which is as good as it gets.
What size should my profile picture be?
Upload 320 x 320. There is no preset for it, so type the numbers into the By Pixels tab — and remember it displays as a circle, so keep the subject clear of the corners.
Can I prepare a week of posts at once?
Queue up to ten images and apply one preset to the whole set. One shape per run, though — separate the squares from the portraits, or the shared crop box will treat them differently.
Does this tool send my photos anywhere?
No. The resizing happens inside your browser, so the first server your photo ever touches is Instagram's, at the moment you choose to post it.