# Heygen Lipsync - Precision API

> Vuelve a doblar un video existente con audio nuevo mediante el modo de sincronización labial de mayor precisión

Sustituye el audio de un video de origen y ajusta el movimiento de la boca para que coincida. Requiere `video_url` y `audio_url`. Los ajustes opcionales incluyen generación de subtítulos, duración dinámica para adaptarse al audio nuevo, eliminación de la pista de música de fondo, mejora de voz y `start_time` y `end_time` para sincronizar solo una parte del clip. Esta es la variante orientada a la precisión.

- Model id: `heygen/v3/lipsync/precision`
- Made by: HeyGen
- Category: Lipsync & Avatars
- Output: video
- Price per second of your output video: $0.10 / second of output video (cheapest run $0.10 (100 API credits))
- Run: `POST https://api.doitong.com/v1/run/heygen/v3/lipsync/precision`
- Quote: `POST https://api.doitong.com/v1/quote/heygen/v3/lipsync/precision`
- Docs page: https://doitong.com/es/developers/models/heygen/v3/lipsync/precision

## Pricing

Price: **$0.10 / second of output video**. Price per second of your output video: the input files are measured before the run (length, resolution, frame rate). The quote measures the same files and is exactly what the run charges.

The full example input below costs $1.00 = 1000 API credits (10 s output video × $0.10).

Prices are the upstream price in USD, paid from the API balance in API credits (1000 API credits = 1 USD). `POST https://api.doitong.com/v1/quote/heygen/v3/lipsync/precision` with the same JSON body returns the exact price for that input; the quote is exactly what a run charges. Invalid input is never charged and failed or canceled requests are refunded automatically.

## Input parameters

Send either the canonical name or the native field name (not both). Canonical names are the same across models.

| Parameter | Canonical name | Type | Required | Default | Allowed values / range | Description |
|---|---|---|---|---|---|---|
| `video_url` | `video` | string (video URL) | yes |  |  | URL del video de origen para la sincronización labial. |
| `audio_url` | `audio` | string (audio URL) | yes |  |  | URL del archivo de audio de reemplazo. |
| `title` |  | string \| null | no |  |  | Nombre opcional de la tarea de sincronización labial. |
| `enable_caption` |  | boolean | no | `false` |  | Controla si el video de salida incluye subtítulos generados. |
| `enable_dynamic_duration` |  | boolean | no | `true` |  | Permite cambiar la duración para ajustarla al audio de reemplazo. |
| `disable_music_track` |  | boolean | no | `false` |  | Controla la eliminación de la música de fondo del video de origen. |
| `enable_speech_enhancement` |  | boolean | no | `false` |  | Controla la mejora de calidad del audio de reemplazo. |
| `start_time` |  | number \| null | no |  | ≥ 0 | Punto inicial de la sincronización labial parcial, medido en segundos. |
| `end_time` |  | number \| null | no |  | ≥ 0 | Punto final de la sincronización labial parcial, medido en segundos. |

File parameters (`video`, `audio`) take a public `https://` URL, a `data:` URI up to 10 MB, or the `file_url` of an upload from `POST /files`.

## Example input

Required parameters only:

```json
{
  "video": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
  "audio": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
}
```

A fuller example:

```json
{
  "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
  "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
}
```

## Run it

Set `DOITONG_API_KEY` to a key from https://doitong.com/developers/dashboard#keys. `?wait=20` returns the finished request in the same call when it is ready within 20 seconds; otherwise poll `GET /requests/{id}` (it also accepts `?wait=`), or pass `webhook_url`.

### curl

```bash
# Run the model; wait up to 20 s for the finished result in the same call
curl -X POST "https://api.doitong.com/v1/run/heygen/v3/lipsync/precision?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  }'

# Still "queued" or "running"? Poll with the id from the response:
curl "https://api.doitong.com/v1/requests/REQUEST_ID?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY"
```

### JavaScript

```javascript
const API = "https://api.doitong.com/v1";
const headers = {
  "Authorization": "Bearer " + process.env.DOITONG_API_KEY,
  "Content-Type": "application/json",
};

// Run the model; wait up to 20 s for the finished result in the same call
let res = await fetch(API + "/run/heygen/v3/lipsync/precision?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  }),
});
let request = await res.json();
if (!res.ok) throw new Error(request.error.code + ": " + request.error.message);

// Not finished yet: long-poll until it is
while (request.status === "queued" || request.status === "running") {
  res = await fetch(API + "/requests/" + request.id + "?wait=20", { headers });
  request = await res.json();
}
if (request.status !== "succeeded") throw new Error(JSON.stringify(request.error));
console.log(request.outputs.map((o) => o.url), request.cost.credits + " API credits ($" + request.cost.usd + ")");
```

### Python

```python
import os
import requests

API = "https://api.doitong.com/v1"
headers = {"Authorization": "Bearer " + os.environ["DOITONG_API_KEY"]}

payload = {
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/heygen/v3/lipsync/precision", params={"wait": 20}, json=payload, headers=headers)
request = r.json()
if not r.ok:
    raise RuntimeError(request["error"]["code"] + ": " + request["error"]["message"])

# Not finished yet: long-poll until it is
while request["status"] in ("queued", "running"):
    request = requests.get(API + "/requests/" + request["id"], params={"wait": 20}, headers=headers).json()
if request["status"] != "succeeded":
    raise RuntimeError(request["error"])
print([o["url"] for o in request["outputs"]], request["cost"]["credits"], "API credits", "$" + request["cost"]["usd"])
```

### MCP

The MCP server at `https://api.doitong.com/v1/mcp` exposes the tools `search_models`, `get_model`, `quote`, `run`, `get_request`, `cancel_request`, `list_requests`, `create_upload` and `get_account`. A `run` call for this model:

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "run",
    "arguments": {
      "model_id": "heygen/v3/lipsync/precision",
      "input": {
        "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
        "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
      },
      "wait_seconds": 20
    }
  }
}
```

## Response

Every call returns a request object. `status` is one of `queued`, `running`, `succeeded`, `failed`, `canceled`. `outputs` lists the generated files with URLs on our storage (kept forever, or 7 days with `?storage=temporary`; `storage` says which); `output` is the model's own result object with the same URLs.

```json
{
  "id": "req_8k2m4q7x1z9c3v5b6n0p2r4t",
  "object": "request",
  "model": "heygen/v3/lipsync/precision",
  "status": "succeeded",
  "created_at": "2026-10-20T12:00:00Z",
  "started_at": "2026-10-20T12:00:02Z",
  "completed_at": "2026-10-20T12:00:09Z",
  "queue_position": null,
  "cost": {
    "credits": 1000,
    "usd": "1.00",
    "charged": 1000,
    "refunded": 0
  },
  "input": {
    "video_url": "https://content.doitong.com/video/showcase/v3/gen_fox_cartoon.mp4",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  },
  "output": {
    "video": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp4",
      "content_type": "video/mp4",
      "file_name": "0-output.mp4",
      "file_size": 1843200
    },
    "caption_file": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp4",
      "content_type": "video/mp4",
      "file_name": "0-output.mp4",
      "file_size": 1843200
    }
  },
  "outputs": [
    {
      "type": "video",
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp4",
      "content_type": "video/mp4",
      "file_size": 1843200,
      "width": 1280,
      "height": 720,
      "duration": 5,
      "stored": true
    }
  ],
  "error": null,
  "metrics": {
    "inference_seconds": 6.8
  },
  "urls": {
    "self": "https://api.doitong.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t",
    "cancel": "https://api.doitong.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t/cancel"
  }
}
```

### Output fields (`output`)

| Field | Type | Description |
|---|---|---|
| `video` | object {url, content_type, file_name, file_size} | Archivo de video con movimientos labiales sincronizados con el audio de reemplazo. |
| `caption_file` | object {url, content_type, file_name, file_size} \| null | Archivo de subtítulos generado si `enable_caption` está habilitado y HeyGen devuelve un archivo. |

## Related models

- [Heygen Lipsync - Speed](https://doitong.com/developers/models/heygen/v3/lipsync/speed.md) (`heygen/v3/lipsync/speed`): $0.05 / second of output video
- [Kling AI Avatar 2.0 Pro](https://doitong.com/developers/models/kling-video/ai-avatar/v2/pro.md) (`kling-video/ai-avatar/v2/pro`): $0.115 / second of input audio
- [Sync Lipsync 3](https://doitong.com/developers/models/sync-lipsync/v3.md) (`sync-lipsync/v3`): $8.00 / minute of output video
- [VEED Fabric 1.0](https://doitong.com/developers/models/veed/fabric-1.0.md) (`veed/fabric-1.0`): from $0.08 / second of input audio
- [Heygen v5 Digital Twin](https://doitong.com/developers/models/heygen/avatar5/digital-twin.md) (`heygen/avatar5/digital-twin`): $0.10 / second of input audio
- [Heygen · Avatar3 · Digital Twin](https://doitong.com/developers/models/heygen/avatar3/digital-twin.md) (`heygen/avatar3/digital-twin`): $0.034 / second of input audio
- [Heygen · Avatar4 · Digital Twin](https://doitong.com/developers/models/heygen/avatar4/digital-twin.md) (`heygen/avatar4/digital-twin`): $0.10 / second of input audio
- [Heygen · Avatar4 · Image to Video](https://doitong.com/developers/models/heygen/avatar4/image-to-video.md) (`heygen/avatar4/image-to-video`): $0.10 / second of input audio

## Links

- HTML page: https://doitong.com/developers/models/heygen/v3/lipsync/precision
- All models and guides for AI agents: https://doitong.com/developers/llms.txt
- OpenAPI 3.1 with this model's typed request body: https://doitong.com/developers/openapi.json?model=heygen/v3/lipsync/precision
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.com/v1/models/heygen/v3/lipsync/precision