Video

HeyGen Lipsync Speed

Credit-based pricing. Supports reference video.

Try HeyGen Lipsync Speed →Compare models

Output

video

Inputs

Reference audio (required)
Reference video (required)

Example prompt

Re-dub any speaking video with a new audio track — HeyGen Speed delivers fast, natural lip sync

Try this prompt →

LLM-ready

API & LLM schema

Exact request contract for this model. Agents can fetch it from /api/v1/models?id=fal-ai/heygen/v3/lipsync/speed.

POST/api/v1/generate18 fields · 3 required

Field	Type	Requirement	Contract
`model_id`	constant	Required	ArtEmotion model identifier.
`extra`	object	Optional	Model-specific settings may also be nested here.
`max_credits`	number	Optional	Reject before submission if the estimated list price exceeds this cap. · Range: 1–…
`webhook_url`	string	Optional	Format: uri
`webhook_secret`	string	Optional	Optional model input.
`folder_id`	string	Optional	Optional model input.
`prompt`	string	Optional	Optional model input.
`start_time`	number	Optional	Start time in seconds for partial lipsync. · Range: 0–…
`end_time`	number	Optional	End time in seconds for partial lipsync. · Range: 0–…
`disable_music_track`	boolean	Optional	Remove background music from the source video. · Default: false
`enable_dynamic_duration`	boolean	Optional	Allow duration adjustment to match the new audio. · Default: true
`enable_caption`	boolean	Optional	Generate captions in the output video. · Default: false
`enable_speech_enhancement`	boolean	Optional	Enhance the replacement audio quality. · Default: false
`fps_mode`	string	Optional	Frame rate handling for the output video. · Allowed: , vfr, cfr, passthrough · Default:
`keep_the_same_format`	boolean	Optional	Preserve the source video's resolution and bitrate. · Default: false
`title`	string	Optional	Optional title for the lipsync job.
`video_url`	string	Required	Format: uri
`audio_url`	string	Required	Format: uri

Minimal request example

{
  "model_id": "fal-ai/heygen/v3/lipsync/speed",
  "video_url": "https://example.com/video",
  "audio_url": "https://example.com/audio"
}

Raw JSON Schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://www.artemotion.ai/api/v1/models?id=fal-ai%2Fheygen%2Fv3%2Flipsync%2Fspeed",
  "title": "HeyGen Lipsync Speed generation request",
  "description": "Request body accepted by POST /api/v1/generate for fal-ai/heygen/v3/lipsync/speed.",
  "type": "object",
  "properties": {
    "model_id": {
      "type": "string",
      "const": "fal-ai/heygen/v3/lipsync/speed",
      "description": "ArtEmotion model identifier."
    },
    "extra": {
      "type": "object",
      "additionalProperties": true,
      "description": "Model-specific settings may also be nested here."
    },
    "max_credits": {
      "type": "number",
      "minimum": 1,
      "description": "Reject before submission if the estimated list price exceeds this cap."
    },
    "webhook_url": {
      "type": "string",
      "format": "uri",
      "maxLength": 2048
    },
    "webhook_secret": {
      "type": "string",
      "maxLength": 512
    },
    "folder_id": {
      "type": "string"
    },
    "prompt": {
      "type": "string"
    },
    "start_time": {
      "title": "Start Time",
      "description": "Start time in seconds for partial lipsync.",
      "type": "number",
      "minimum": 0
    },
    "end_time": {
      "title": "End Time",
      "description": "End time in seconds for partial lipsync.",
      "type": "number",
      "minimum": 0
    },
    "disable_music_track": {
      "title": "Disable Music Track",
      "description": "Remove background music from the source video.",
      "default": false,
      "type": "boolean"
    },
    "enable_dynamic_duration": {
      "title": "Enable Dynamic Duration",
      "description": "Allow duration adjustment to match the new audio.",
      "default": true,
      "type": "boolean"
    },
    "enable_caption": {
      "title": "Enable Caption",
      "description": "Generate captions in the output video.",
      "default": false,
      "type": "boolean"
    },
    "enable_speech_enhancement": {
      "title": "Enable Speech Enhancement",
      "description": "Enhance the replacement audio quality.",
      "default": false,
      "type": "boolean"
    },
    "fps_mode": {
      "title": "FPS Mode",
      "description": "Frame rate handling for the output video.",
      "default": "",
      "type": "string",
      "enum": [
        "",
        "vfr",
        "cfr",
        "passthrough"
      ]
    },
    "keep_the_same_format": {
      "title": "Keep Same Format",
      "description": "Preserve the source video's resolution and bitrate.",
      "default": false,
      "type": "boolean"
    },
    "title": {
      "title": "Title",
      "description": "Optional title for the lipsync job.",
      "type": "string"
    },
    "video_url": {
      "type": "string",
      "format": "uri"
    },
    "audio_url": {
      "type": "string",
      "format": "uri"
    }
  },
  "required": [
    "model_id",
    "video_url",
    "audio_url"
  ],
  "additionalProperties": false
}

Browse schemas for every ArtEmotion model →

FAQ

How much does HeyGen Lipsync Speed cost on ArtEmotion?

Credit-based pricing. You pay in ArtEmotion credits — every plan and top-up converts USD to credits at a fixed rate.

Do I get my credits back if HeyGen Lipsync Speed fails?

Yes — failed generations are never charged. The credits are released back to your balance automatically.

Can I call HeyGen Lipsync Speed from the API?

Yes. Use POST /api/v1/generate with model_id: "fal-ai/heygen/v3/lipsync/speed". See the API reference for the full schema.

Where are my generations stored?

Every output is saved to your personal Library. You can export or delete everything any time from Privacy & deletion.

Ready to generate with HeyGen Lipsync Speed?

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No commitment. New accounts get 50 free credits on signup. See pricing.