How to sync audio and video in iMovie with a clapperboard

Before you start

These steps follow Apple's iMovie guides for iPhone and Mac. You'll be matching the first frame where the sticks close (or the first white frame of a flash) with the very start of the clap's spike. New to that? Read how to sync audio and video with a clapperboard.

Sync in iMovie on iPhone

1. Put the playhead on the clap

   Open your movie project and move the playhead to the frame where the sticks close. A short sound file lands at the playhead, which saves dragging.

2. Add the sound file

   Tap Add Media (+), then Files, and choose your recording.

3. Make it movable

   If the clip went in as background music (green, at the start of the project), tap it, tap Actions, then Foreground. Now you can move it freely.

4. Zoom in

   Pinch open on the timeline until the frames around the clap are easy to see.

5. Drag it into place

   Touch and hold the sound clip until it lifts, then drag it so the start of the clap spike sits under the clap frame.

6. Mute the camera's sound

   Tap the video clip, open its audio controls and tap Mute. Or tap Actions, then Detach, and delete the camera's sound clip.

Sync in iMovie on Mac

1. Show the waveforms

   Drag the video into the timeline, click Settings at the top right of the timeline and tick Show Waveforms.

2. Attach the sound under the clip

   Drag your sound file from the Finder and drop it just under the video clip, so a small bar connects them. Don't drop it in the background music area: sound there doesn't move with the video.

3. Find the clap frame

   Zoom in with Command-plus or a trackpad pinch. Step one frame at a time with the Left and Right arrow keys to the first closed-sticks frame.

4. Drag the sound into place

   Drag the attached sound clip until the start of its clap spike lines up with the playhead.

5. Mute the camera's sound

   Select the video clip and press Shift-Command-M. Or choose Modify > Detach Audio (Option-Command-B) and delete the camera's sound clip.

What iMovie can't do

• No automatic sync on iPhone, iPad or Mac. Every take is lined up by dragging.
• No way to nudge a sound clip one frame at a time, so zoom in as far as you can before the final drag.
• Check each take on a close-up of someone talking. Two or three frames off is easy to see on lips.

For a whole day of takes, an editor with automatic sync, like DaVinci Resolve (free) or Final Cut Pro, will save time. See how to sync audio in DaVinci Resolve.

Questions