Instagram Post Size: Dimensions for Photos and Carousels

Instagram post sizes at a glance

Instagram's Help Center gives one rule for an IG post size: a width of up to 1080 pixels and an aspect ratio between 1.91:1 and 3:4. These are the width and height pairs inside that range at the full 1080 pixel width.

Landscape (1.91:1) and tall portrait (3:4) are the two limits Instagram states, and a photo outside them is cropped. Square and 4:5 heights are worked out from the ratio and the 1080 pixel width. If you publish through a scheduling tool, read the API section below first: its range ends at 4:5, not 3:4.

Is the tallest post 4:5 or 3:4?

Instagram's Help Center says 3:4. Its range runs from 1.91:1 to 3:4, so a 1080 × 1440 photo keeps its original resolution. If another size guide gives 1080 × 1350 (4:5) as the tallest option, the Help Center says otherwise: 1350 is the right height for 4:5, but 4:5 is not the upper limit in the app.

One route stops at 4:5: publishing through the Instagram API, the way apps publish to professional accounts. See "Posting through the API or a scheduler" below.

What Instagram does with other photo sizes

Instagram says it uploads photos at the best quality it can, up to a width of 1080 pixels. What happens to your file depends on its width and ratio:

• Width between 320 and 1080 pixels, ratio from 1.91:1 to 3:4: the photo keeps its original resolution.
• Wider than 1080 pixels: Instagram sizes it down to a width of 1080 pixels.
• Narrower than 320 pixels: Instagram enlarges it to a width of 320 pixels.
• Ratio outside 1.91:1 to 3:4: Instagram crops the photo to fit a supported ratio.

To get a width of 1080 pixels, upload a photo that is at least 1080 pixels wide with a ratio inside the range, using the latest version of the app.

Some common ratios against that range:

Instagram's Help Center says reels accept ratios from 1.91:1 to 9:16, a wider range than photo posts. For reel sizes, see the Instagram Reel size guide.

Carousel size

A carousel is a post with up to 20 photos and videos. Two rules from Instagram matter for the size:

• You choose one orientation, square, portrait or landscape, and it applies to every photo and video in the post. You cannot pick a different orientation for each one.
• You can drag each item inside the frame to change how it is cropped.

So the carousel dimensions are the dimensions of the format you pick. If you design the slides yourself, make every slide the same size so each one fits the single frame the post uses, for example 1080 × 1350 pixels for portrait, 1080 × 1080 for square or 1080 × 566 for landscape. The feed shows the first item with a row of dots under it. If you have one wide picture to cut into equal slides, the free image splitter does it in your browser. For ideas on what to put on the slides, see the Instagram carousel guide, and for the steps to add several photos, see how to post multiple photos on Instagram.

Posting through the API or a scheduler

Apps publish to Instagram professional accounts through the content publishing API, which has tighter rules than the app. Meta's developer documentation lists these for images:

• Format: JPEG only.
• File size: 8 MB at most.
• Aspect ratio: 4:5 to 1.91:1, so 1080 × 1350 is the tallest at a 1080 pixel width and a 3:4 photo is outside the range.
• Width: 320 to 1440 pixels; Meta scales a file up or down to fit.

For carousels, the API allows up to 10 items rather than 20, and it crops every image to the shape of the first one, with 1:1 as the default. A scheduling tool built on that API can inherit these limits, so check the tool's own help before you design around 1080 × 1440 or a 20-slide carousel.

File types

When you post from a computer, Instagram's Help Center lists jpg, png and heic/heif as the supported file formats. The API route above takes JPEG only.

Instagram post size in inches

Instagram's help pages give sizes in pixels and aspect ratios. They do not list a size in inches, because a pixel has no fixed physical size until you pick a resolution. To convert, divide the pixels by the PPI (pixels per inch) your design tool uses. This table uses 300 PPI as an example:

At 72 PPI the same 1080 × 1350 file measures 15 × 18.75 inches. The inch figure changes with the PPI, but the post stays 1080 × 1350 pixels, so design in pixels.

Profile grid thumbnails

Instagram's Help Center does not document how a post is cropped on the profile grid, so this guide gives no grid size. Instagram's August 2015 announcement of portrait and landscape posts said they appear on the grid as a center-cropped square. Several third-party size guides, including SocialBu's and RecurPost's, report that the grid now previews a taller 3:4 tile, but no Instagram page we found confirms it. To see what your own grid does, publish a test post and look at its tile.

Sources and last check

The sizes on this page come from these pages, read on October 19, 2026:

• Image resolution of photos you share on Instagram
• Share a post with multiple photos or videos on Instagram
• Post a photo on Instagram
• Content publishing with the Instagram Platform and IG User Media, Meta's developer documentation
• Reel size and aspect ratios on Instagram
• Landscape and portrait formats on Instagram, Instagram's 2015 announcement

Square and 4:5 heights, the 16:9 and 4:3 sizes and the inch figures are calculated from the stated ratios and the 1080 pixel width. Instagram can change its limits, so check its Help Center if a figure matters to you.