3:4 vs 4:5 on Instagram: which aspect ratio should you choose in 2026?

Between 3:4 and 4:5 on Instagram, the difference comes down to height: 1080 × 1440 px for 3:4, 1080 × 1350 px for 4:5. In 2026, 3:4 is the logical choice if your photos come from a smartphone or if you want profile thumbnails that match your posts; 4:5 still makes sense for continuing an existing series or for photos that are a little less tall. Both are portrait formats, and both take up far more height in the feed than square or landscape.

3:4 and 4:5: the differences in pixels

The two formats share the same recommended width, 1080 px. Only the height changes:

• 4:5: 1080 × 1350 px;
• 3:4: 1080 × 1440 px, or 90 px more in height.

The gap is modest, a little under 7% more height. To the eye, 3:4 looks slightly more slender and 4:5 slightly more compact. Neither is "better" in itself: what matters is what you fit into the frame and what you're forced to cut.

4:5 is Instagram's long-standing portrait: for years it was the tallest format accepted in the feed. 3:4 has been accepted since 2025. The Instagram size guide for 2026 lists every dimension, including square, landscape and story.

The 3:4 format and the profile grid

Since 2025, the profile grid has shown vertical 3:4 thumbnails, where they used to be square. That's the main argument for 3:4: a post in this format has exactly the proportions of its thumbnail. What you compose is what people see on your profile, with no surprises.

A 4:5 image doesn't have quite those proportions. Its thumbnail can't reproduce it exactly, and an element placed right next to an edge, a headline or a logo for example, may not come across well there. The workaround is simple: whatever the format, keep text and important subjects in the center of the image, away from the edges.

If the visual consistency of your profile matters to you (shop, portfolio, brand account), this point carries a lot of weight. An Instagram grid planner lets you see your next posts as 3:4 thumbnails before publishing them. If your posts are mostly seen in the feed, it carries less.

When to choose 3:4

Your photos come from a smartphone. Most phones shoot in 4:3 proportions by default, which gives 3:4 when you hold the device vertically. A photo like that fits a 3:4 frame with nothing lost, whereas a 4:5 frame forces you to trim a band off the top or bottom.

You care about your grid. Thumbnail and post have the same proportions: the grid shows your images the way you composed them.

Your subject is vertical. A full-length portrait, architecture, an outfit, a dish shot from above with context around it: the extra 90 px give it room to breathe.

You're starting a new series. With no history to stay consistent with, you might as well adopt the format that matches the current grid.

When to stick with 4:5

You're continuing an existing series. If your templates, brand visuals or older carousels are in 4:5, switching midway creates a break. The consistency of a series is worth more than 90 px.

Your photos are less tall. A camera photo with a 3:2 ratio, held vertically, gives 2:3: it has to be cropped in both formats. A square or landscape photo, on the other hand, loses less on the sides in 4:5 than in 3:4.

You're splitting a panorama. For the same number of slides, 4:5 covers a slightly wider composition: four slides in 4:5 form a 3.2:1 ratio, versus 3:1 in 3:4. Depending on your photo's ratio, one or the other will be the closer fit; the article on how to post a panorama on Instagram has the full table.

Comparison table: 3:4 vs 4:5

3:4 or 4:5 in a carousel: the first-image rule

In a carousel, the question only comes up once: every image takes the format of the first one, and the others are cropped to match. Mixing a 3:4 image with 4:5 images means letting Instagram cut for you, with no control over what disappears.

For a seamless carousel, the rule is even stricter: the slightest difference in height or framing between two slides breaks the seam. Choose the format before you compose, and export all the images in one go. In the SwipeAtelier editor, the format is set for the whole carousel and the carousel templates are calculated for that format and that number of slides: there's no risk of mixing.

The seamless carousel guide covers what comes next, from picking a template to posting.

Our recommendation, with nuance

For a new post with no particular constraint, go with 3:4: it matches the profile grid and phone photos. For a series already established in 4:5, stay in 4:5 for as long as consistency matters to you, and switch when you start a new series rather than in the middle of one. To get the same photo in both formats and compare, resize photos for Instagram in 4:5 and 3:4 at once.

Either way, the result depends more on composition than on the 90 px gap: a clear subject, enough margin, one format across the whole carousel.