---
title: "Create Lipsync"
method: POST
path: "/v3/lipsyncs"
tags: ["Lipsync"]
---

# Create Lipsync

`POST /v3/lipsyncs`

Replaces the audio on an existing video and re-animates the speaker's lip movements to match the new audio. Use mode: 'speed' for fast output or 'precision' for high-quality lip-sync.

## Headers

- `Idempotency-Key` string

## Request body

- CreateLipsyncRequest — Request body for POST /v3/lipsyncs.
  - `video` union, required — Source video — provide as {type: 'url', url: '...'} or {type: 'asset_id', asset_id: '...'}
    - AssetUrl — Asset input via publicly accessible HTTPS URL.
      - `type` 'url', required — Input type discriminator
      - `url` string, required — Publicly accessible HTTPS URL for the asset
    - AssetId — Asset input via HeyGen asset ID from the asset upload endpoint.
      - `type` 'asset_id', required — Input type discriminator
      - `asset_id` string, required — HeyGen asset ID from the asset upload endpoint
  - `audio` union, required — Replacement audio — provide as {type: 'url', url: '...'} or {type: 'asset_id', asset_id: '...'}
    - AssetUrl — Asset input via publicly accessible HTTPS URL.
      - `type` 'url', required — Input type discriminator
      - `url` string, required — Publicly accessible HTTPS URL for the asset
    - AssetId — Asset input via HeyGen asset ID from the asset upload endpoint.
      - `type` 'asset_id', required — Input type discriminator
      - `asset_id` string, required — HeyGen asset ID from the asset upload endpoint
  - `title` string, nullable — Title for the lipsync job
  - `mode` 'speed' | 'precision'
  - `callback_url` string, nullable — Webhook URL for completion notifications
  - `callback_id` string, nullable — ID included in webhook payload
  - `enable_caption` boolean — Generate captions for the output video
  - `keep_the_same_format` boolean, nullable — Preserve the source video's encoding specs (resolution, bitrate).
  - `enable_dynamic_duration` boolean — Allow dynamic duration adjustment
  - `disable_music_track` boolean — Remove background music
  - `enable_speech_enhancement` boolean — Enhance speech quality
  - `enable_watermark` boolean — Add watermark to output
  - `start_time` number, nullable — Start time in seconds for partial lipsync
  - `end_time` number, nullable — End time in seconds for partial lipsync
  - `fps_mode` string, nullable — Frame rate mode: 'vfr', 'cfr', or 'passthrough'.
  - `folder_id` string, nullable — Project/folder ID to organize lipsync into

## Response `200`

Successful response

- object
  - `data` LipsyncCreateResponse — Response for POST /v3/lipsyncs.
    - `lipsync_id` string, required — Lipsync ID — use GET /v3/lipsyncs/{id} to poll status

## Other responses

- `400` — Invalid request parameters
- `401` — Authentication failed
- `409` — A prior request with this Idempotency-Key is still in progress. Wait for the original request to complete, then retry.
- `429` — Rate limit exceeded

---

[API](https://skmtc.net/heygen/apis/heygen-external-api.md) · [All operations](https://skmtc.net/heygen/apis/heygen-external-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/heygen/heygen-external-api/revisions/e2e54726e210/schema)