Footage without a voice feels like a rough cut; the voiceover is what makes it feel finished. If recording your own means a mic you don't own and ten takes you don't want to do, here's how to add a clean AI voiceover instead — including the mixing trick that keeps it from sounding pasted on.
Script to the footage, not the other way around
Watch the clip first and write to what's on screen, noting roughly where each line should land. Keep it conversational and a touch shorter than feels right — a little breathing room beats a wall of narration, and viewers process spoken words differently than written ones.
Pick the voice, then stop fiddling
Choose a voice that fits the mood — calm for a tutorial, upbeat for a promo — and lock it in. A Narration or Conversational preset is plenty; resist micromanaging settings before you've heard the voice against your footage.
Generate, then fix by ear
Export the narration as an MP3 and play it over the video. Hear an awkward line? Adjust that sentence's punctuation or respell a stumble and regenerate only it. You'll usually touch two or three spots at most.
Sync it in your editor
Drop the MP3 on its own track in CapCut, Premiere, or DaVinci and slide lines to hit the visuals. The habit that makes it sound pro: duck any background music down 6-12 dB under the voice, so narration stays clear on phone speakers.
Then localize it for near-free reach
Once the first cut is done, regenerate the script in other languages or dub the whole video — same effort, several new audiences. It's the cheapest growth move most creators never bother to make.