Instagram Post Resizer

The recommended size changed, and the grid changed with it

The 4:5 portrait at 1,080 by 1,350 pixels is now the recommended Instagram feed size, rather than the square that was the default for years. It fills the most vertical space in the feed, which is where attention is won on a phone, and it keeps most of the image visible in the profile. The more consequential change is the grid itself. Since the 2025 update the profile grid previews posts at 3:4 rather than 1:1, which means a square post now loses its sides in the grid. An older grid built on square posts shows visibly side cropped previews as a result.

RecurPost: Instagram post size guide, updated September 2026

Upload size and preview size are different things

The distinction that resolves most of the confusion is that you upload at 4:5 and Instagram previews in the grid at about 3:4. The grid trims roughly 67 pixels of width from a 1,080 pixel wide post, which is enough to clip a logo placed near the edge or a line of text that ran close to the boundary. That is why centring the focal point matters more on Instagram than the upload ratio does, and it is why a square post feels wrong in the grid even though nothing about the upload is technically incorrect. Planning the next grid at 4:5 with a centred subject is the adjustment that makes a profile read cleanly again.

• Upload at 1,080 × 1,350 (4:5); the grid previews at about 1,013 × 1,350 (3:4).
• The grid trims roughly 67 px of width from a 1,080 px post.
• Keep logos, faces, and text near the centre, not the edges.
• A square upload is not wrong, it just crops on the sides in the grid.

NoteUpload at 4:5, expect a 3:4 grid preview. Centring the subject covers both.

Why 4:5 beats square and landscape

A 4:5 portrait takes the most vertical space of the three feed shapes, and vertical space is what a scrolling phone feed rewards. It also retains more of the image in the 3:4 grid than a square does, because 4:5 and 3:4 are close ratios, whereas trimming a square to 3:4 removes a visible band from both sides. Landscape is the weakest of the three by a wide margin, occupying the least feed space of any, so it is worth using only when repurposing a wide asset such as a blog header and the small footprint is acceptable. Square still has a place when the same asset is being reused across networks and a uniform shape matters more than feed real estate.

• 4:5 claims the most vertical space in the feed.
• 4:5 also keeps more of the image in the 3:4 grid than 1:1 does.
• Landscape has the smallest footprint of the three feed shapes.
• Square is reasonable when one asset is reused across several networks.

Note4:5 wins twice: most feed space, and least loss in the 3:4 grid.

Resizing to the new default

Almost nothing is 4:5 by default, so a resize is needed for most source images, and the fitting mode is the decision. A landscape photo is wider than 4:5, so filling the frame crops the sides, which usually works when the subject is centred. A portrait phone photo may be taller than 4:5, so filling crops the top and bottom, and a screenshot is often tall enough that the text ends up small. Where the subject position matters, crop it yourself first, where you can see what is being kept, and then resize. Instagram scales every upload to a maximum width of 1,080 pixels, so exporting at that width avoids a second scaling step.

• A landscape photo: fill crops the sides. Usually correct for a centred subject.
• A tall portrait: fill crops top and bottom, and screenshots lose legibility.
• Crop yourself with the image cropper when placement matters.
• Instagram scales to a maximum width of 1,080 px, so export at that width.