In a nutshell
A carousel is a format that shows many images or videos in one post, swiped sideways. The name comes from the amusement park merry-go-round and describes the way items come around in order. The caption (the text), and the likes and comments, are shared by the whole post.
Number of items by network
| Network | Items per post | Mix images and video |
|---|---|---|
| 20 | Yes | |
| Threads | 20 | Yes |
| Facebook Pages | 10 | No |
| 9 | No | |
| X | 4 | No |
These numbers are the values SNS TOWN confirmed in each company's developer documentation and uses in the composer (as of October 2026). Instagram's Help also says you can share up to 20 photos and videos in one post (Share multiple photos and videos).
How to make people keep swiping
A carousel's results are decided by whether the first slide makes people want to see more. Put a conclusion or a question on the first slide, and show the content in order from the second. Placing a summary or the next step (such as a link to the booking page) on the last slide keeps readers from getting lost at the end.
It suits topics whose meaning comes across by viewing them in order, such as the steps of making a dish, before and after a renovation, a product in different colors, or frequently asked questions at one per slide. On the other hand, cramming in many loosely related photos blurs what you want to show. Keeping to one theme per post keeps even a long carousel easy to read.
The aspect ratio of images should basically be the same within a post. On Instagram, the ratio of the first image is applied to the others. How to decide ratios is covered in Image and video sizes for each network, and how to make images in How to make social media images.
In SNS TOWN
The composer switches how many items can be attached, and whether images and video can be mixed, to match the network of the account selected in the header. How to attach images is explained in Attaching images and videos.
Try it free for 7 days. No credit card required.
Start free
