Updated October 2026
Instagram carousels have specific per-slide pixel dimensions that determine how much of each slide is visible in-feed before cropping. This page is a reference for the exact sizes this site's carousel splitter uses, and why those particular numbers.
This is the tallest aspect ratio Instagram currently allows for an in-feed post (a 4:5 ratio). It gives you the most vertical space per slide of any standard in-feed format, which is why it's the default preset in this tool — more vertical room means more room for text overlays, taller subjects, or simply a larger-looking image occupying more of the viewer's screen while scrolling.
The classic 1:1 square format. It crops less aggressively from a wide source image than portrait does (less height to fill relative to width), and it's the most predictable format if your source image's composition is close to square already. Square carousels also tile more predictably if you're ever building a 3x3 or similar visual grid across multiple posts.
This preset does no cropping at all: it computes a slide height purely from your uploaded image's own aspect ratio and the total composite width (1080px × your slide count), preserving every pixel of your original image. The tradeoff is that the resulting per-slide height won't necessarily match a "named" Instagram size — useful when preserving the exact original composition matters more than fitting a standard template.
| Format | Per-slide size | Aspect ratio | Total canvas (4 slides) |
|---|---|---|---|
| Portrait | 1080 × 1350 px | 4:5 | 4320 × 1350 px |
| Square | 1080 × 1080 px | 1:1 | 4320 × 1080 px |
| Fit Original | 1080 × (source-dependent) | Matches source | 4320 × (source-dependent) |
"Total canvas" is the full composite width/height this tool scales your source image to "cover" before slicing it into equal segments — see the seamless slicing explainer for exactly how that works.
1080 pixels is Instagram's standard base resolution for both portrait and square posts — uploading at exactly this width avoids any additional downscaling or recompression by Instagram's own upload pipeline, which can otherwise introduce slight quality loss on images uploaded at a different resolution.