---
title: "Extend Music"
method: POST
path: "/api/v1/generate/extend"
---

# Extend Music

`POST /api/v1/generate/extend`

## Request body

- object
  - `defaultParamFlag` boolean, required — Controls parameter usage mode. - `true`: Use custom parameters (requires `continueAt`, `prompt`, `style`, and `title`). - `false`: Use original audio parameters (only `audioId` is required).
  - `audioId` string, required — Audio ID of the track to extend. This is the source track that will be continued.
  - `prompt` string — Description of how the music should be extended. Required when defaultParamFlag is true.
  - `style` string — Music style, e.g., Jazz, Classical, Electronic
  - `title` string — Music title
  - `continueAt` number — The time point (in seconds) from which to start extending the music. - Required when `defaultParamFlag` is `true`. - Value range: greater than 0 and less than the total duration of the generated audio. - Specifies the position in the original track where the extension should begin.
  - `personaId` string — Only available when custom parameters are enabled. Persona ID to apply to the generated music. Optional. You can use either: - A Persona ID generated by the [Generate Persona](https://docs.sunoapi.org/suno-api/generate-persona) endpoint. Use `personaModel: style_persona` or omit `personaModel` to use the default. - A `voiceId` generated by the [Suno Voice](https://docs.sunoapi.org/suno-api/suno-voice-generate) workflow. When using a voice-generated ID, you must set `personaModel: voice_persona`.
  - `personaModel` 'style_persona' | 'voice_persona' — Persona model type to apply when using `personaId`. Optional. - `style_persona` (default): Use this for Persona IDs generated by the Generate Persona endpoint. - `voice_persona`: Use this when `personaId` is a `voiceId` generated by Suno Voice. This option is only available with V5 and V5_5 models.
  - `model` 'V4' | 'V4_5' | 'V4_5PLUS' | 'V4_5ALL' | 'V5' | 'V5_5', required — Model version to use, must be consistent with the source audio. - Available options: - **`V5_5`**: Unleash Your Voice: Custom Models Tailored to Your Unique Taste. - **`V5`**: Superior musical expression, faster generation. - **`V4_5PLUS`**: V4.5+ is richer sound, new waysto create, max 8 min. - **`V4_5ALL`**: V4.5-all is better song structure, max 8 min. - **`V4_5`**: V4.5 is smarter prompts, fastergenerations, max 8 min. - **`V4`**: V4 is improved vocal quality,max 4 min.
  - `negativeTags` string — Music styles to exclude from generation
  - `vocalGender` 'm' | 'f' — Preferred vocal gender for generated vocals. Optional.
  - `styleWeight` number — Weight of the provided style guidance. Range 0.00–1.00.
  - `weirdnessConstraint` number — Constraint on creative deviation/novelty. Range 0.00–1.00.
  - `audioWeight` number — Weight of the input audio influence (where applicable). Range 0.00–1.00.
  - `callBackUrl` string, uri, required — The URL to receive task completion notifications when music extension is complete. - For detailed callback format and implementation guide, see [Music Extension Callbacks](https://docs.sunoapi.org/suno-api/extend-music-callbacks) - Alternatively, you can use the get music generation details endpoint to poll task status

## Response `200`

Request successful

- object
  - `code` 200 | 400 | 401 | 404 | 405 | 413 | 429 | 430 | 455 | 500 — # Status Codes - ✅ 200 - Request successful - ⚠️ 400 - Invalid parameters - ⚠️ 401 - Unauthorized access - ⚠️ 404 - Invalid request method or path - ⚠️ 405 - Rate limit exceeded - ⚠️ 413 - Theme or prompt too long - ⚠️ 429 - Insufficient credits - ⚠️ 430 - Your call frequency is too high. Please try again later. - ⚠️ 455 - System maintenance - ❌ 500 - Server error
  - `msg` string — Error message when code != 200
  - `data` object
    - `taskId` string — Task ID for tracking task status

## Other responses

- `500` — Server error

---

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