The short answer
A carousel is 2 to 10 items and can mix photos and videos in one post. The API builds each item separately, then publishes them as a single post — so a scheduler has to handle a multi-step upload correctly, and not all of them do.
Step by step
1Prepare 2 to 10 items
Instagram's limit is 10. Keep every item the same aspect ratio, or Instagram crops to the first item's shape and your later slides lose their edges.
2Upload them in order
Order is fixed at creation. The first item is the one that appears in your grid and in the feed, so it carries the whole post.
3Write one caption
A carousel has a single caption for the whole post, not one per slide.
4Schedule it
snazzy creates each item, then the parent post, then publishes — and if a step fails partway it resumes from where it stopped rather than re-uploading and orphaning what already succeeded.
What catches people out
- Mixed photo and video in one carousel is supported by Instagram, but several schedulers only accept images. Worth testing before you plan content around it.
- You cannot reorder or add slides after publishing. Only the caption is editable.
- A partly-created carousel that fails midway can leave unused containers on Instagram's side. They expire on their own, but a tool that re-uploads from scratch on every retry will burn through your publishing quota.
Related guides
Last checked 2026-09-01. Instagram changes its API without notice — if something here is wrong, tell us and we will fix it.
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