The short answer: use 1080 × 1350 pixels (4:5 portrait) for every slide in an Instagram carousel in 2026. It fills the most screen, Instagram doesn’t crop it, and it works for both photos and design-heavy slides.

Here’s the complete picture.

Instagram carousel dimensions at a glance

Format	Size (px)	Aspect ratio	Notes
Portrait (recommended)	1080 × 1350	4:5	Most screen real estate in feed
Square	1080 × 1080	1:1	The classic, still fully supported
Landscape	1080 × 566	1.91:1	Smallest presence; avoid for carousels

Two rules matter more than any single number:

Every slide in one carousel must share the same aspect ratio. Instagram sizes the whole carousel from the first slide. Mixing ratios gets later slides cropped.
Width is fixed at 1080 px on export. Upload larger and Instagram downscales (fine); upload smaller and it upscales (blurry).

Why 4:5 portrait wins

A 4:5 post occupies roughly 25% more vertical screen than a square post and more than double a landscape one. In a feed that’s scrolled with a thumb, held pixels are held attention — which is why nearly every high-performing carousel account switched to 4:5.

The only reason to prefer square is if you re-post the same asset somewhere that requires 1:1, and you’d rather not export twice.

Safe zones: where not to put text

Instagram overlays UI on top of your slides:

Bottom ~250 px: caption preview, page dots, and action icons can overlap here on some devices. Keep headlines and CTAs above this band.
Top ~180 px: the account name overlays the top-left on the first slide in some placements.
Horizontal edges: keep 60–80 px of padding so text never touches the bezel.

A simple layout rule that respects all of this: center your content block, keep 80 px side margins, and put nothing critical in the top or bottom 15% of the slide.

Export settings that keep slides sharp

Export at 1080 × 1350 exactly, or an exact 2× (2160 × 2700) — never odd sizes that force resampling.
Use JPG at 80–90% quality for photo-heavy slides, PNG for flat design and text (crisper edges, no compression artifacts around type).
Keep files under 8 MB per image (Instagram’s cap. Most exports land well under).
sRGB color profile. Wide-gamut exports get flattened and can shift colors.

How many slides?

Instagram allows up to 20 slides per carousel (raised from 10 in 2024). Engagement data consistently shows a sweet spot of 6–10 slides: enough to earn a second impression when Instagram re-serves the carousel from a later slide, short enough that swipe-through survives.

The boring part, automated

Getting sizes right once is easy. Getting them right on every slide of every post, thirty times a month, is where feeds drift into inconsistency. CarouselMaker renders every slide at 1080 × 1350 with safe zones baked into the template, so every post ships at the right size without anyone checking export settings. See how it works →