# How to lip sync a video with AI

> Lip sync a video with AI by giving a tool a clear clip and new audio, so it redraws the mouth. Tools, steps, credit costs and a note on Hindi.
- **Author**: Marxx
- **Published**: 2026-11-13
- **Category**: Video editing
- **URL**: https://marxx.ai/library-guides/how-to-lip-sync-a-video-with-ai

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To lip sync a video with AI, give a tool a clear clip and new audio, and it redraws the mouth. Use it when you dub an ad, so the lips follow the new words.

## Tools with lip sync

| Tool | How it does lip sync | Note (checked 3 Nov 2026) |
|---|---|---|
| HeyGen | In translated and generated videos | Hindi (India) is on its video translation list. Free plan: 3 videos a month, 1 minute each, with a watermark |
| Captions (by Mirage) | Lipdub adjusts the lips to dubbed audio | Its help centre lists Hindi and Hinglish |
| Synthesia | Dubbing with optional lip sync | 80 credits a minute with lip sync, 40 without |
| Kapwing | Lip sync videos | Listed on its Business plan |

For the idea behind it, read [what AI lip sync is](/glossary/ai-lip-sync) and [what AI dubbing is](/glossary/ai-dubbing).

We make Marxx. The Generate tab in [Marxx's AI video editor](/features/ai-video-editor) lists lip sync and dubbing into another language. Both use credits and sit on Match, $29 a month at launch prices (checked 3 Nov 2026).

## Steps

1. Choose a clip where one face is clear and the mouth is visible.
2. Make the new audio. Translate the script, or record or generate the voiceover. See [how to dub ads into Hindi](/guides/how-to-dub-ads-into-hindi) and [how to clone your voice for ads](/guides/how-to-clone-your-voice-for-ads).
3. Upload the clip and the audio. Turn lip sync on.
4. Watch the result with sound on. Look hard at the mouth on the first and last lines.
5. Read every price, name and number against your script. Fix the script and run it again if one is wrong.
6. Export 9:16 and add captions.

## A worked example

Say you dub a 2-minute ad. Synthesia lists 80 credits a minute with lip sync and 40 without.

- With lip sync: 2 x 80 = 160 credits
- Without: 2 x 40 = 80 credits

Lip sync doubles the cost here. Use it on the shots where the speaker's mouth is on screen. Skip it where a voiceover plays over B-roll.

## FAQ

### Does lip sync work in Hindi?

HeyGen lists Hindi (India) for video translation. Captions lists Hindi and Hinglish in its help centre. Test a short clip first.

### Do I need lip sync for every dubbed ad?

No. If the speaker's mouth is not in shot, a plain dub is enough. On Synthesia, a dub without lip sync costs half as many credits.

### Is there a free option?

HeyGen's free plan gives 3 videos a month, up to 1 minute each, with a watermark. Check that it includes the lip sync you need.

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