Auto captions for Reels and TikTok, made on your Mac

Instagram and TikTok can caption your video after you upload it. Captioning it yourself first gives you a look you control and one file that works on every platform.

In-app captions or burned-in captions?

TikTok and Instagram both have auto-caption features inside their apps. They're convenient, but the look is theirs, you correct them on a phone keyboard, and the captions belong to that one upload: post the same clip to Shorts and you start again.

Burned-in captions are part of the video. They look the same everywhere, you can proofread them on a big screen, and the file is ready for every platform.

Make a captioned Reel or TikTok with Stillreel

Import your clip (MP4, MOV or M4V; iPhone HEVC footage works) and trim the start and end, or split out the parts you don't want.
Transcribe. Captions are generated on your Mac in about a second for a short clip on Apple silicon.
Correct. Click any caption to fix a word. Nudge timing by a frame if a caption starts early.
Style. Pick one of five looks:
- Bold Pop: big, upper-case, outlined, with a highlighted word.
- Karaoke: highlights each word as it is spoken.
- Boxed: white text on a dark box, readable over busy footage.
- Clean and Minimal: quieter styles.
Frame. Choose 9:16, then crop and pan, or use a blurred background.
Export an H.264 MP4. There's no watermark.

Then move the file to your phone (AirDrop is quickest) and post it, or upload it from the platform's website. Stillreel doesn't post for you and doesn't need your social accounts.

What the export looks like

1080×1920 pixels, H.264 video with AAC audio, in an MP4 file.
The frame rate of your footage (24, 25, 29.97 and 30 fps tested), at a constant rate even if the phone recorded a variable one.
In our tests: no dropped or duplicated frames at cuts, and audio in sync to within a fraction of a millisecond.

Where to put captions

Both apps cover the bottom of the screen with the caption, the sound name and the buttons, and the right edge with likes and comments. The middle position stays clear of all of that. Top works for clips where a face sits low in the frame.

Tips

Keep captions to one or two short lines; viewers read them while scrolling.
Karaoke-style highlighting helps people follow fast speech.
Check the first two seconds closely; that is where most viewers decide to stay.
Export an SRT too if you're also posting a longer version to YouTube.

Stillreel works offline, so you can caption on a train or a plane, and nothing is uploaded until you choose to post.

Common questions

Does the same file work for Reels, TikTok and Shorts? Yes. All three accept a 9:16 MP4 at 1080×1920, so one export can go to each. Keep the clip within each platform's current length limit.

Can I make a square version for the feed as well? Switch the format to 1:1 and export again; the captions and edit stay the same.

Will captions survive the platform's compression? Burned-in captions are part of the picture, so they look as sharp as the rest of the video. The bolder styles (Bold Pop, Boxed) hold up best on small screens.

Try Stillreel free for 14 days

Every feature, no watermark, nothing uploaded. Then $24 (launch price until 2026-11-30, then $29) once if you keep it.

Download the free trial Buy for $24