Name: MusicGen API: Text to Music Generator by Meta
Brand: magicapi
SKU: api-magicapi-music-generation-api-meta-musicgen
Availability: InStock
Author: API Market

Shashank Agarwal

# 🎼 Text-to-Music Generator API (Meta MusicGen)

## Overview
MusicGen is a music generation model from Meta. It generates music from a prompt or melody.

Describe the music in `prompt` and set the length in seconds with `duration`. Add an `input_audio` file to have the result follow its melody, or set `continuation` to `true` to continue the clip. Each request returns the URL of one audio file.

## Features
- **Four model versions**: `stereo-melody-large` (default), `stereo-large`, `melody-large` and `large`.
- **Text to music**: describe style, instruments and mood in `prompt`.
- **Melody input**: send `input_audio` and the generated music follows its melody.
- **Continuation**: set `continuation` to `true` to extend `input_audio`, using the part between `continuation_start` and `continuation_end`.
- **Length**: `duration` in seconds (default 8).
- **Sampling controls**: `top_k` (default 250), `top_p` (default 0), `temperature` (default 1), `classifier_free_guidance` (default 3) and `seed`.
- **Output**: `wav` (default) or `mp3`, with `loudness`, `clip`, `peak` or `rms` normalization.

## Use Cases
1. **Background music**: short clips for videos, games and apps.
2. **Melody variations**: new arrangements that follow the melody of a recorded tune.
3. **Extending clips**: continue an existing audio clip with more music in the same style.
4. **Sound sketches**: try out musical ideas from a text description.

## Visual Examples
### Example Input
Prompt: "Edo25 major g melodies that sound triumphant and cinematic. Leading up to a crescendo that resolves in a 9th harmonic"

Other fields: `model_version` `stereo-large`, `duration` `8`, `output_format` `mp3`, `normalization_strategy` `peak`, `continuation` `false`, `continuation_start` `0`, `multi_band_diffusion` `false`, `top_k` `250`, `top_p` `0`, `temperature` `1`, `classifier_free_guidance` `3`.

### Example Output
[Listen to the example output](https://blog.api.market/wp-content/uploads/2026/10/musicgen-output-b7py4df3-api-market.mp3)

## Input Parameters
| Field | Type | Required | Default | Allowed values | Description |
| --- | --- | --- | --- | --- | --- |
| `model_version` | string | No | `stereo-melody-large` | `stereo-melody-large`, `stereo-large`, `melody-large`, `large` | Model to use for generation |
| `prompt` | string | No | none |  | A description of the music you want to generate. |
| `input_audio` | string (URL) | No | none |  | Audio file URL that influences the generated music. If `continuation` is `true`, the generated music continues the audio file. Otherwise it follows the audio file's melody. |
| `duration` | integer | No | `8` |  | Duration of the generated audio in seconds. |
| `continuation` | boolean | No | `false` |  | If `true`, the generated music continues from `input_audio`. Otherwise it follows `input_audio`'s melody. |
| `continuation_start` | integer | No | `0` | `0` or more | Start time of the audio file to use for continuation. |
| `continuation_end` | integer | No | none | `0` or more | End time of the audio file to use for continuation. If -1 or not set, the end of the audio clip is used. |
| `multi_band_diffusion` | boolean | No | `false` |  | If `true`, the EnCodec tokens are decoded with MultiBand Diffusion. Only works with non-stereo models. |
| `normalization_strategy` | string | No | `loudness` | `loudness`, `clip`, `peak`, `rms` | Strategy for normalizing audio. |
| `top_k` | integer | No | `250` |  | Reduces sampling to the k most likely tokens. |
| `top_p` | number | No | `0` |  | Reduces sampling to tokens with cumulative probability of p. When set to `0` (default), top_k sampling is used. |
| `temperature` | number | No | `1` |  | Controls the 'conservativeness' of the sampling process. Higher temperature means more diversity. |
| `classifier_free_guidance` | integer | No | `3` |  | Increases the influence of inputs on the output. Higher values produce lower-variance outputs that follow the inputs more closely. |
| `output_format` | string | No | `wav` | `wav`, `mp3` | Output format for generated audio. |
| `seed` | integer | No | none |  | Seed for the random number generator. If not set or -1, a random seed is used. |

## Pricing
- **Pay As You Go (PAYG) pricing**: you only pay for what you use.
- **Price**: $0.059 per API unit.
- **1 API unit = 1 request with up to 37 seconds of processing time.** A longer request uses one unit per started 37-second block (for example, 38 to 74 seconds of processing is 2 units).
- Longer `duration` values take longer to process and can use more units.
- **Example cost**: the example request (8 seconds of music) took 20.1 seconds of processing, 1 unit: **$0.059**.
- **Failed or cancelled predictions are not billed.**
- **GET requests to check prediction status** are free and don't count toward API unit usage.
- **No monthly subscription fee.**

## API Documentation

### Base URL
All API requests go to: `https://prod.api.market/api/v1/magicapi/music-generation-api-meta-musicgen`

### Authentication
Send your api.market API key in the `x-api-market-key` header:
```
x-api-market-key: YOUR_API_MARKET_KEY
```

### Asynchronous Processing
**IMPORTANT**: This API is asynchronous. The flow is:
1. Send a POST request to `/predictions`. A successful request returns **201 Created** with a prediction `id` and a `status` of `starting` or `processing`.
2. Poll GET `/predictions/{id}` with that ID.
3. Keep polling while `status` is `starting` or `processing`.
4. Stop when `status` is `succeeded` (read `output`), `failed` or `canceled` (read `error`).

A polling interval of 2 seconds and an overall timeout of 600 seconds (10 minutes) work well.

### Endpoints

#### Create a Prediction
```bash
curl -X POST "https://prod.api.market/api/v1/magicapi/music-generation-api-meta-musicgen/predictions" \
  -H "Content-Type: application/json" \
  -H "x-api-market-key: YOUR_API_MARKET_KEY" \
  -d '{
    "version": "671ac645ce5e552cc63a54a2bbff63fcf798043055d2dac5fc9e36a837eedcfb",
    "input": {
      "top_k": 250,
      "top_p": 0,
      "prompt": "Edo25 major g melodies that sound triumphant and cinematic. Leading up to a crescendo that resolves in a 9th harmonic",
      "duration": 8,
      "temperature": 1,
      "continuation": false,
      "model_version": "stereo-large",
      "output_format": "mp3",
      "continuation_start": 0,
      "multi_band_diffusion": false,
      "normalization_strategy": "peak",
      "classifier_free_guidance": 3
    }
  }'
```

Response (201 Created):
```json
{
  "id": "b7py4df33hrna0d1c6mtfngydr",
  "version": "671ac645ce5e552cc63a54a2bbff63fcf798043055d2dac5fc9e36a837eedcfb",
  "status": "starting",
  "created_at": "2026-10-22T03:31:26.303Z"
}
```

#### Check Prediction Status
```bash
curl -X GET "https://prod.api.market/api/v1/magicapi/music-generation-api-meta-musicgen/predictions/{id}" \
  -H "x-api-market-key: YOUR_API_MARKET_KEY"
```

Response when the prediction has finished (200 OK):
```json
{
  "id": "b7py4df33hrna0d1c6mtfngydr",
  "status": "succeeded",
  "output": "https://blog.api.market/wp-content/uploads/2026/10/musicgen-output-b7py4df3-api-market.mp3",
  "error": null,
  "created_at": "2026-10-22T03:31:26.303Z",
  "started_at": "2026-10-22T03:31:26.803Z",
  "completed_at": "2026-10-22T03:31:46.944Z"
}
```

`output` is a single URL string pointing to the generated audio file.

### Status Codes
- **201 Created**: prediction created (POST `/predictions`). This is the normal success response.
- **200 OK**: prediction details returned (GET `/predictions/{id}`).
- **400 Bad Request**: invalid input, for example a `model_version` or `output_format` that is not in the list.
- **401 Unauthorized**: missing or invalid API key.
- **404 Not Found**: no prediction with that ID.
- **429 Too Many Requests**: rate limit exceeded.
- **500 Internal Server Error** or **503 Service Unavailable**: temporary server problem; retry later.

## Rate Limits
All plans allow 10 requests per second. Requests above that return `429 Too Many Requests`; back off before retrying and honour any `Retry-After` header. Polling a prediction with GET is free but still counts toward the per-second limit, so poll every 1 to 5 seconds rather than in a tight loop.
## Error Handling
- Check the HTTP status code of every request and read the response body for the error message.
- A prediction can also end with `status` set to `failed`; the `error` field then explains why. Failed predictions are not billed.
- Retry 429, 500 and 503 responses with exponential backoff. Fix the input before retrying a 400.

## Implementation Guide
### Example Code

#### JavaScript
```javascript
const apiKey = "YOUR_API_MARKET_KEY";
const baseUrl = "https://prod.api.market/api/v1/magicapi/music-generation-api-meta-musicgen";

async function createAndWaitForPrediction(input) {
  const response = await fetch(`${baseUrl}/predictions`, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      "x-api-market-key": apiKey
    },
    body: JSON.stringify({ version: "671ac645ce5e552cc63a54a2bbff63fcf798043055d2dac5fc9e36a837eedcfb", input })
  });

  if (response.status !== 201) {
    throw new Error(`API error: ${response.status} ${await response.text()}`);
  }

  const prediction = await response.json();
  return pollForResults(prediction.id);
}

const delay = (ms) => new Promise((resolve) => setTimeout(resolve, ms));

async function pollForResults(predictionId) {
  const maxTimeout = 600000;
  const pollInterval = 2000;
  const startTime = Date.now();

  while (Date.now() - startTime < maxTimeout) {
    const response = await fetch(`${baseUrl}/predictions/${predictionId}`, {
      headers: { "x-api-market-key": apiKey }
    });

    if (!response.ok) {
      throw new Error(`API error: ${response.status} ${await response.text()}`);
    }

    const prediction = await response.json();

    if (prediction.status === "succeeded") {
      return prediction.output;
    }

    if (prediction.status === "failed" || prediction.status === "canceled") {
      throw new Error(`Prediction ${prediction.status}: ${prediction.error || "Unknown error"}`);
    }

    await delay(pollInterval);
  }

  throw new Error("Prediction timed out after 10 minutes");
}

createAndWaitForPrediction({
    "top_k": 250,
    "top_p": 0,
    "prompt": "Edo25 major g melodies that sound triumphant and cinematic. Leading up to a crescendo that resolves in a 9th harmonic",
    "duration": 8,
    "temperature": 1,
    "continuation": false,
    "model_version": "stereo-large",
    "output_format": "mp3",
    "continuation_start": 0,
    "multi_band_diffusion": false,
    "normalization_strategy": "peak",
    "classifier_free_guidance": 3
  }).then((output) => console.log(output));
```

#### Python
```python
import time
import requests

API_KEY = "YOUR_API_MARKET_KEY"
BASE_URL = "https://prod.api.market/api/v1/magicapi/music-generation-api-meta-musicgen"


def create_and_wait_for_prediction(input_data):
    headers = {"Content-Type": "application/json", "x-api-market-key": API_KEY}
    response = requests.post(
        f"{BASE_URL}/predictions",
        headers=headers,
        json={"version": "671ac645ce5e552cc63a54a2bbff63fcf798043055d2dac5fc9e36a837eedcfb", "input": input_data},
    )

    if response.status_code != 201:
        raise Exception(f"API error: {response.status_code} {response.text}")

    return poll_for_results(response.json()["id"])


def poll_for_results(prediction_id):
    max_timeout = 600
    poll_interval = 2
    headers = {"x-api-market-key": API_KEY}
    start_time = time.time()

    while time.time() - start_time < max_timeout:
        response = requests.get(f"{BASE_URL}/predictions/{prediction_id}", headers=headers)

        if response.status_code != 200:
            raise Exception(f"API error: {response.status_code} {response.text}")

        prediction = response.json()

        if prediction["status"] == "succeeded":
            return prediction["output"]

        if prediction["status"] in ("failed", "canceled"):
            raise Exception(f"Prediction {prediction['status']}: {prediction.get('error') or 'Unknown error'}")

        time.sleep(poll_interval)

    raise Exception("Prediction timed out after 10 minutes")


print(create_and_wait_for_prediction({
    "top_k": 250,
    "top_p": 0,
    "prompt": "Edo25 major g melodies that sound triumphant and cinematic. Leading up to a crescendo that resolves in a 9th harmonic",
    "duration": 8,
    "temperature": 1,
    "continuation": False,
    "model_version": "stereo-large",
    "output_format": "mp3",
    "continuation_start": 0,
    "multi_band_diffusion": False,
    "normalization_strategy": "peak",
    "classifier_free_guidance": 3
}))
```

## FAQ
- **How do I make the music follow a melody?**
  - Send the melody as `input_audio` with a `melody` model version (`stereo-melody-large` or `melody-large`) and leave `continuation` set to `false`.
- **How do I extend an existing clip?**
  - Send it as `input_audio`, set `continuation` to `true`, and optionally set `continuation_start` and `continuation_end`.
- **Can I use MultiBand Diffusion?**
  - Only with the non-stereo versions (`melody-large` and `large`). Set `multi_band_diffusion` to `true`.
- **How is a request priced?**
  - $0.059 per started 37 seconds of processing. Short clips such as the 8-second example use one unit.
- **Is the 201 response from POST an error?**
  - No. 201 Created means the prediction was accepted. Use the returned `id` to poll GET `/predictions/{id}` until `status` is `succeeded`, `failed` or `canceled`.
- **What if my prediction fails?**
  - Failed predictions are not billed. Read the `error` field, adjust the input and try again.

## Contact Us
If you have any questions or need assistance, you can reach out to us through the embedded chat on the bottom right corner of the page or send an email to hello@magicapi.com.


MusicGen API by Meta: generate music from a text prompt, follow the melody of an input audio file or continue a clip, as WAV or MP3. Pay as you go.