An Instagram carousel takes up to 20 items, pictures, videos or a mix, through the publishing API as well as in the app. Each picture is a JPEG up to 8 MB with a ratio from 3:4 to 1.91:1, and Instagram crops every slide to the shape of the first one, with 1:1 as the default. The figures changed in 2026: until October a tool that followed Meta's older reference stopped at 10 items and 4:5, and a live test on 30 October 2026 showed what Instagram really takes.
Carousel size at a glance
| Rule | |
|---|---|
| Items | 2 to 20, pictures, videos or both |
| Picture format | JPEG only |
| Picture size | 8 MB each |
| Picture ratio | 3:4 to 1.91:1 for each |
| Recommended size | 1080 × 1350 (4:5) or 1080 × 1440 (3:4) for every slide |
| Width | 320 to 1,440 pixels; outside that Instagram scales it |
| Crop | Every slide is cropped to the first one; 1:1 if you do not choose |
| Caption | 2,200 characters, 30 hashtags, 20 mentions |
| Alt text | Per picture |
| Counts as | One post against the daily limit |
What the live test found
On 30 October 2026, with the Instagram account of the Test workspace, connected through Instagram Login:
| Test | Result |
|---|---|
| 11 items | Published |
| 15 items | Published |
| 20 items (17 pictures and 3 videos) | Published |
| 21 items | Refused: "too many attachments to qualify as a carousel" |
| A 3:4 picture (1080 × 1440) as the first slide | Published and shown uncropped |
| 4:5, 1:1 and 1.91:1 | Published |
| 1.95:1, 2:1, 1:2 and 1:3 | Refused (error 2207009) |
Meta's content-publishing guide says carousels are limited to 20. Its media reference still says pictures must be within 4:5 to 1.91:1, which the 3:4 test did not bear out. 2:3 and 9:16 passed the creation of the container, but publishing them was not confirmed, so Preflight still refuses those two shapes in a carousel.
Choosing a size
- Pick one shape and use it for every slide. Meta crops later slides to the first one. If the first is 3:4 and the second is 1:1, the second loses its top and bottom, and text near an edge can be cut.
- 3:4 gives the most screen and fills a profile grid tile with no crop, according to third-party guides; Instagram has no official page that says so. 4:5 is a little shorter and always accepted.
- Keep the subject in the middle. It survives a square, a 4:5 or a 3:4 crop alike.
- Export a JPEG in sRGB. A PNG or WebP is refused by the API; Preflight makes a JPEG copy for Instagram when you upload one, upright and with white behind any transparency, and keeps your original.
The sizes of a single picture, and why a tall poster is refused, are on the Instagram post size page.
Videos inside a carousel
A carousel can mix videos with pictures, as the 20-item test did with three videos. Each video follows the Reel rules for its own length, size and frame rate, and a Reel as such cannot be placed inside a carousel. Reel-only settings (cover, trial, collaborators) are ignored on a carousel, and Preflight says so before sending. See the Reel size page.
Limits around a carousel
| Posts a day through the API | 100 per account when read on 30 October 2026; a carousel counts as one |
| Hashtags | 30 through the API; the Instagram app allows 5 per post since December 2025 |
| A prepared but unpublished carousel | Expires after 24 hours, so a tool prepares it close to the time |
| First comment | Posted straight after the carousel |
How Preflight handles it
The composer checks every file of the carousel, up to twenty, for format, size and ratio and names the one that fails. Files past the twentieth are named as not sent. Preflight creates one container per item, waits for each to finish, builds the carousel container and publishes it at the scheduled minute. It works on every plan, the free one included, and over the API. The step-by-step is in how to schedule an Instagram carousel, and the container flow in the Graph API guide. All networks' counts side by side: images per post.
Figures from Meta's Instagram documentation and live publishes of 30 October 2026.
Questions people ask
- How many photos can you post on an Instagram carousel?
- Up to 20, pictures, videos or a mix, both in the app and through the publishing API. A live test on 30 October 2026 published 20 items and refused 21.
- What size should Instagram carousel slides be?
- 1080 × 1350 (4:5) or 1080 × 1440 (3:4), as JPEG up to 8 MB, the same shape for every slide. Instagram crops every slide to the first one, with 1:1 as the default.
- Does Instagram accept 3:4 pictures in a carousel?
- Yes. A 1080 × 1440 picture was published as the first slide and shown uncropped in a live test on 30 October 2026, although Meta's media reference still says 4:5. Shapes taller than 3:4 are refused.
- Can a carousel mix pictures and videos?
- Yes. Each video follows the Reel rules for its length, size and frame rate. A Reel cannot be placed inside a carousel.
- Why did my carousel fail to publish?
- Usually a picture is not a JPEG, is over 8 MB or has a ratio outside 3:4 to 1.91:1, there are more than 20 items, or a video has the wrong frame rate. Preflight checks every item before sending and names the one that fails.