From slides to post text, in one voice
Every carousel the AI makes opens with its caption already written. For one you built yourself, a single click drafts it.
- 01
Switch the editor to Caption
The top bar has two modes: Design for the slides and Caption for the text that goes with the post. In Caption mode the left side is your caption and the right side is a live picture of the post on the app, on a desktop or a phone, in light or dark.
- 02
Your writer drafts it from your slides
Click Write it for me and the writer who wrote your slides writes the caption too, in the same voice. Under the box you’ll see “Written by Mia to match your slides”. Prefer your own words? Just type: the post on the right updates as you go.
- 03
Keep the hook above “…more”
A dashed line with a small “…more” tag marks the exact place the app will cut your caption. It moves with the platform, the device and light or dark view. Under the caption, Other first lines offers up to three new openings: click one to swap it in. Still stuck? Borrow one of 50 hooks to fill in.
- 04
Change it with a click, or in your own words
The Rewrite menu works on the words you select or on the whole caption: Rewrite, Shorter, Longer, Simpler, More specific, Stronger first line, Add a call to action, Add hashtags and Fix grammar, plus a Tone group. Or type a request in the bar under the box, like “make it shorter and add a question”. Each AI change uses 1 AI edit and comes with Undo.
- 05
Check it, copy it, post it
The Ready to post? checklist under the caption flags a missing caption, one over the limit, a first line cut by “…more” and too many hashtags. Click Copy to paste it into the app, or copy it from the window that opens after you download. Posting to your LinkedIn profile from aiCarousels takes the caption with it. For the whole route, see turning a finished carousel into a post.
Inside every platform’s limit
There is one caption per project. Switch the platform at the top of the editor and the counter, the “…more” line and the checks follow it, while your words stay the same.
Caption limits and checks in aiCarousels
| Platform | Caption limit | Before “…more” | Hashtag check |
|---|---|---|---|
| 3,000 characters | About 3 lines (phones cut earlier) | None | |
| 2,200 characters | About 2 lines, after your username | Warns over 30 | |
| TikTok | 4,000 characters | About 2 lines | Warns over 10 |
| X | 280 characters | The first 280, then “Show more” | None |
| Threads | 500 characters | The whole post, no cut | None |
The limits the app’s counter uses. Going over turns the counter red and adds a blocking line to the checklist.
The small things that make a caption easy to read
Bold and italic
The buttons appear when the caption is for LinkedIn, X or Threads. They use special characters that work on letters A to Z and numbers.
Three kinds of list
Turn lines into a bullet, numbered or arrow list. Click again to take it off.
Arrange lines by length
Shortest to longest, longest to shortest, longest in the middle or at the ends.
Emoji, one click
A small grid of the ones people use most: pointing hands, ticks, fire, lightbulbs and numbers.
Hashtags that fit
Add hashtags asks the AI for fitting ones. The checklist says 3 to 5 good ones work better than 30.
The real post beside it
See the caption on the app as you type: desktop or phone, light or dark.
Sometimes the caption is the post
Write a LinkedIn text post
The same writers write posts without slides, with three first lines to choose from. When one does well, one click turns it into a carousel.
Your caption is cut after a few lines. Here’s how to make those lines count.
