Two methods depending on the type of video
Translating a video with AI actually covers two fairly different approaches, and the one to pick depends on what the original video shows.
Method 1 — Extract, translate, regenerate the voice
For a video where the voiceover isn't synced to a face shown in close-up (illustration footage, an edited montage, an avatar filmed from behind), the simplest method is to extract the original script, translate it, then generate a new voiceover in the target language and lay it over the existing video. No lip resync is needed in this case.
Method 2 — Video translation with lip resync
When a face is talking in close-up on screen, simply swapping the audio track creates a visible mismatch between the lips and the new language. AI video translation with lip resync adjusts lip movement to match the new audio track — the most convincing method for this scenario, and one of the most reliable use cases for this technology today.
Which method to choose
| Type of video | Method |
|---|---|
| Voiceover over illustration / edited footage | Extract, translate, regenerate the voice |
| Speaking face in close-up | Video translation with lip-sync |
| Existing AI avatar | Regenerate with the translated script |
Points to watch
An automatic translation gives a good starting point, but it's worth a human proofread before generating the voice: the rhythm of a literally translated sentence doesn't always match the original intent. And as with any realistic AI video or voice content, the EU AI Act requires disclosing that a video was translated and lip-resynced by AI whenever the result could pass for an original recording in that language.
What ToolAcces already covers
ToolAcces combines ElevenLabs for multilingual speech synthesis and HeyGen for video translation with lip resync — the two methods described above, bundled in a single subscription. See also our AI avatar guide for creating an avatar you can reuse across languages.
Frequently asked questions
No, only if the speaking face stays visible on screen in close-up. For a video that's mostly voiceover over illustration footage, simply swapping in the translated audio track is enough.
It gives a good starting point, but a human proofread is still recommended before generating the voice — a literal translation can produce a sentence rhythm that no longer matches the original intent.
Yes, and it's actually one of the strongest use cases: an avatar created once can then be produced in several languages from the same translated script, with no new recording session needed.
Go further
- AI avatar: creating your digital twin
What an AI avatar can actually do today (training, LinkedIn, sales), its limits, and how to create one without filming anything.
- AI voice or human voiceover: what's the difference for a professional video?
Where AI wins by a wide margin (cost, turnaround, revisions), where human voiceover keeps a real edge, and how to decide based on your project rather than on principle.
- Free or paid AI video generator: which one should you start with?
What free plans actually limit (watermark, duration, quota), and at what point a subscription becomes more cost-effective than stacking free accounts.
- How to edit and automatically subtitle an AI-generated video?
The complete guide to the most decisive and most overlooked step: assembling clips, pacing the edit, generating readable subtitles for sound-off viewing, and exporting watermark-free.
See exactly what ToolAcces includes — credited API engines and mutualized access, in a single subscription starting at €39.99/month, no commitment. View pricing.