How do I put an AI voiceover into iMovie?
Create the narration with Speechma Pro’s Text to speech, download the MP3, and import it into iMovie. Apple lists M4A, MP4, MP3, WAV and AIFF as audio formats you can add, so Speechma Pro’s MP3 works on Mac, iPhone and iPad with no conversion. On a Mac you simply drag the file from Finder onto the timeline; on iPhone and iPad you add it through Add Media › Files.
This workflow suits family vacation recaps, school projects, church slideshow videos and small-business promos. You don’t need an external mic, a quiet closet or ten takes of the same sentence. And if you want a different tone, you can switch voices in seconds instead of re-recording.
Step-by-step: add a Speechma Pro voiceover in iMovie
- Edit your video firstLay out your clips in iMovie so you know roughly how long each section is. Narration is easier to write for a finished cut.
- Write and generate the narrationWrite one paragraph per scene and paste it into Speechma Pro. Pick a voice from 1,900+ options, adjust speed and pitch in Voice Effects, and use the pause buttons (or commas for short breaths) to add natural pauses. Click Generate Audio.
- Download the MP3Download each file. On iPhone, Safari saves it to the Files app (usually the Downloads folder in iCloud Drive or On My iPhone).
- Mac: drag the MP3 into the timelineIn Finder, drag the MP3 directly onto the iMovie timeline under the clip where the narration should start. It attaches to that clip and moves with it. For narration that should run under everything, drop it into the background music well instead.
- iPhone/iPad: add it from FilesOpen your project, move the playhead to where the voice should begin, tap the Add Media (+) button, choose Files and select the MP3 from iCloud Drive or another location.
- Trim and position the audioDrag the ends of the audio clip to trim silence, and slide it left or right to sync with the visuals. Split long narration into scenes so each piece stays attached to its clip.
- Balance volume and exportLower the original clip audio or music so the voice is clear, preview with headphones, then share or export your movie.
iMovie audio compatibility and where to place your voiceover
| Option | Details | Best for |
|---|---|---|
| Supported audio formats | M4A, MP4, MP3, WAV, AIFF | Speechma Pro MP3 imports directly |
| Attached to a clip (Mac) | Audio moves when you move that video clip | Scene-by-scene narration |
| Background music well (Mac) | Edited separately below the timeline | One continuous narration or music bed |
| Add Media › Files (iPhone/iPad) | Placed at the playhead from iCloud Drive or Files | Editing on the go |
How do I make the narration fit my clips?
Time each clip first. In iMovie, the duration shows when you select a clip; jot it down next to the matching paragraph of your script. At a normal speaking pace, about two and a half words fill one second, so a 12-second shot of the Grand Canyon fits roughly 25–30 words. If a paragraph runs long, cut words rather than speeding up the voice.
Leave a little air, too. A voice that starts the instant a clip begins and talks until the last frame feels crowded. Start narration about half a second into a shot and let important visuals, like a graduation walk or a first look at a new house, play with music only. Those quiet moments make the narrated parts land harder.
Troubleshooting iMovie voiceovers
- The MP3 won’t appear on my iPhone. Open the Files app and check Downloads. If it’s in a ZIP from “download all,” tap the ZIP to extract it first.
- The narration moved when I rearranged clips. That’s because it was attached to a clip. Place continuous narration in the background music well (Mac) instead.
- The voice is drowned out by clip audio. Select the video clip and lower its volume, or mute it completely for a pure voiceover.
- There’s a gap of silence at the start. Trim the front of the audio clip, or remove the extra comma or ellipsis at the beginning of your script and regenerate.
- The script is too long for one conversion.
Sample script for a 60-second iMovie travel recap
“Day one: we landed in Denver just after sunrise, picked up the rental, and drove straight into the mountains. By noon we were at Estes Park; cold air, blue sky, and elk crossing the road like they owned it! Day two was the hike everyone had been dreading, and secretly looking forward to.”
Notice the semicolon before “cold air” for a medium pause and the exclamation mark for an energetic beat. Generate each day as its own file so you can line it up with the matching clips. For more storytelling voices, try our narrator voice generator.
Frequently asked questions
Can I add an MP3 voiceover to iMovie?
Is Speechma Pro ready to use with iMovie?
Why use an AI voice instead of iMovie’s Record Voiceover?
How do I keep the voiceover in sync when I edit clips?
Can I use a narrator voice in Spanish or another language?
Make better voiceovers, faster
- New voices and features the day they launch
- Script templates and tricks that make AI voices sound human
- Creator stories, community picks and early access