What is frame rate?
Frame rate is the number of still pictures a video shows per second, measured in fps. Common rates: 23.976 for the film look, 25 in Europe, 29.97 or 30 for social, 60 for sports and screen recordings. Cuts can only happen on whole frames — that grid quietly governs every edit.
Why do captions drift out of sync in AI-edited video?
A common cause is fractional cuts. If an editor cuts at 4.63 seconds in a 29.97fps video, there is no frame there — the nearest boundaries are 4.6046 and 4.6380. Software that ignores this rounds each segment's video to the frame grid while keeping audio fractional; ffmpeg's concat then pads each joint with silence. Forty cuts later, the timeline is visibly longer than the cut list says, and every caption timed to the original transcript lands late.
The fix is frame-snapping: quantize every cut boundary to the grid before rendering, so the rendered timeline equals the cut list to the millisecond. Never does this on every splice — it's why word-timed captions stay on-beat without manual nudging, in your locked caption style.
How do frame rates interact with each platform?
| Platform | Recommended | Notes |
|---|---|---|
| TikTok / Reels / Shorts | 30 fps | 60 accepted; 30 is the norm for talking head |
| YouTube long-form | 24 / 30 / 60 fps | match your source; don't resample upward |
| Screen recordings | 60 fps | cursor motion at 30 looks steppy |
Read the transcript
What is frame rate? Frame rate is the number of still pictures a video shows per second, measured in fps. Common rates: 23.976 for the film look, 25 in Europe, 29.97 or 30 for social, 60 for sports and screen recordings. Cuts can only happen on whole frames — that grid quietly governs every edit.
Frequently asked questions
Why is it 23.976 and 29.97 instead of 24 and 30?
A 1950s color-TV compromise: NTSC slowed 30fps by 0.1% to avoid interference between the color and audio carriers. Every 'drop-frame' oddity since descends from that decision.
What happens if a cut doesn't land on a frame boundary?
The video duration snaps to whole frames but the audio doesn't, so each segment's audio runs up to one frame long or short. Concatenation pads the difference with silence — audible dropouts at every joint, and a timeline that stretches a little more with every cut.
Which frame rate should I record in for social video?
30fps is the safe default for talking-head social content; 60fps if you capture fast motion or screen recordings. Consistency matters more than the number — mixing rates in one edit forces resampling.