Fade in / out API

Updated 2026-09-18 · Suno-API team

Endpoint description

Fade in/out adds a fade-in (gradually louder) or fade-out (gradually quieter) effect to an existing song.

Endpoint: POST /api/music/fade

Billing: Paid, billed by the requested model; the amount actually charged follows the back-office price configuration.

Recommended model: suno-v6. suno-v6, suno-v6-wild and suno-v6-mini are available.

Wait times and timeouts (important): this is a synchronous endpoint — the order is only accepted and handed to generation when the response arrives. Measured, most requests return in 1-3 seconds, about 10% take longer than 30 seconds, and the longest is about 230 seconds. Set your client timeout to 300 seconds or more; no response does not mean nothing was generated, and do not retry immediately after a timeout (that duplicates the order and charges again). If the connection dropped, confirm later with GET /api/music/songs. See "Wait times and timeout settings" in the New API overview.

Authentication

Request parameters

Request example

curl -X POST https://www.suno-api.io/api/music/fade \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "suno-v6",
    "source_clip_id": "source_song_id",
    "direction": "out",
    "duration_seconds": 3,
    "song_title": "Faded version"
  }'

Response

{
  "code": 200,
  "message": "success",
  "data": {
    "clips": [
      {
        "song_id": "result_song_id",
        "song_title": "Faded version",
        "status": "processing"
      }
    ]
  }
}

One call returns 1 result (edit actions do not produce 2 songs). Save clips[].song_id and poll the song query API until it reaches completed.

Notes

• direction accepts only in or out; one request can specify one direction.
• duration_seconds must be greater than 0 and is measured in seconds.