POST videos/add-sound

Add sound to Kling video

August 8, 2025 (October 1, 2025)

Request Headers
Request Body
Responses
Model
Examples
Try It

This endpoint generates sound for an existing video using Kling’s AI audio generation capabilities.

Video can’t be shorter than 3 seconds or longer than 20 seconds.

https://api.useapi.net/v1/kling/videos/add-sound

Request Headers

Authorization: Bearer {API token}
Content-Type: application/json
# Alternatively you can use multipart/form-data
# Content-Type: multipart/form-data

API token is required, see Setup useapi.net for details.

Request Body

{
  "video": "https://s21-kling.klingai.com/....mp4",
  "replyUrl": "https://my.domain.com/webhook-endpoint-kling",
  "replyRef": "my-id-1234"
}

email is optional when only one account configured.
However, if you have multiple accounts configured, this parameter becomes required.
video is required, the URL of the video to add sound to.
Video can be uploaded using POST /assets and the returned URL can be used here.
Video can’t be shorter than 3 seconds or longer than 20 seconds.
cropVideoOriginalSound is optional, whether to preserve the original video’s sound.
Default false (original sound will be replaced).
maxJobs is optional, the maximum number of concurrent Kling jobs.
replyUrl is optional, a URL to receive webhooks when the video is completed.
See useapi.net Webhooks.
replyRef is optional, include a custom reference to identify the job.
Passed as-is to the replyUrl webhook.

Responses

200 OK

{
  "task": {
    "id": 1234567890,
    "userId": 12345,
    "type": "kwave_video2audio",
    "scene": "NORMAL_CREATION",
    "status": 5,
    "taskInfo": {
      "type": "kwave_video2audio",
      "inputs": [
        {
          "name": "video",
          "inputType": "URL",
          "token": null,
          "blobStorage": null,
          "url": "https://v15-kling.klingai.com/…",
          "cover": null,
          "fromWorkId": null,
          "fromUploadId": null
        }
      ],
      "arguments": [
        {
          "name": "biz",
          "value": "klingai"
        },
        {
          "name": "imageCount",
          "value": "1"
        },
        {
          "name": "duration",
          "value": "20"
        }
      ],
      "extraArgs": {},
      "callbackPayloads": [
        {
          "name": "video2audio_payloads",
          "resources": [
            {
              "name": "originalVideoUrl",
              "type": "VIDEO",
              "url": "https://v15-kling.klingai.com/…"
            }
          ],
          "arguments": [
            {
              "name": "cropVideoOriginalSound",
              "value": "false"
            }
          ]
        }
      ],
      "scene": "NORMAL_CREATION"
    },
    "favored": false,
    "deleted": false,
    "viewed": false,
    "createTime": 1754630611379,
    "updateTime": 1754630611379,
    "viewTime": 0,
    "status_name": "submitted",
    "status_final": false
  },
  "works": [],
  "status": 5,
  "message": "",
  "limitation": null,
  "userPoints": {
    "points": [
      {
        "orderId": "1234567890",
        "type": "reward",
        "amount": 26600,
        "balance": 3150,
        "startTime": 1754406534079,
        "endTime": 1757084934079
      }
    ],
    "total": 113390
  },
  "userTickets": {
    "ticket": [
      {
        "orderId": "1234456789",
        "type": "priority",
        "packageType": "reward",
        "amount": 1,
        "balance": 1,
        "startTime": 1754406534079,
        "endTime": 1757084934079
      }
    ]
  },
  "editProject": null,
  "status_name": "submitted",
  "status_final": false
}

400 Bad Request

{
  "error": "Invalid video URL format"
}

401 Unauthorized

{
  "error": "Unauthorized",
  "code": 401
}

404 Not Found

Kling was unable to locate one of the referenced assets. Make sure to use POST /assets to upload assets.

{
    "error": "Sorry, the requested resource was not found (VALID.ResourceNotFound)",
    "message": "Not Found"
}

500 Internal Server Error

Kling uses a 500 response to indicate moderation and other issues with the input. It may be hard to separate actual 500 errors from moderation errors, so use the error field text and your best judgement to tell them apart, since the message field most often has very generic and perhaps misleading text.
```
{
  "error": "The content you uploaded appears to violate the community guidelines. (CM_EXT.POther)",
  "message": "Service busy (CM_EXT.POther)"
}
```

When successful, the response includes a task ID which can be used to check the status using GET /tasks/task_id.

Model

{ // TypeScript, all fields are optional
    task: {
        id: number              // Unique task identifier
        userId: number          // User ID
        type: string            // Task type: "kwave_video2audio"
        scene: string           // Scene type: "NORMAL_CREATION"
        status: number          // Task status 
        taskInfo: {
            type: string        // Task type
            inputs: {
                name: string    // Input name: "video"
                inputType: string // Input type: "URL"
                token: string | null
                blobStorage: string | null
                url: string     // Video URL
                cover: string | null
                fromWorkId: number | null
                fromUploadId: number | null
            }[]
            arguments: {
                name: string    // Argument name
                value: string   // Argument value
            }[]
            extraArgs: Record<string, any>
            callbackPayloads: {
                name: string    // "video2audio_payloads"
                resources: {
                    name: string    // "originalVideoUrl"
                    type: string    // "VIDEO"
                    url: string     // Original video URL
                    marginTop?: number
                    countInRow?: number
                    mode?: string
                }[]
                arguments: {
                    name: string    // Parameter name
                    value: string   // Parameter value
                }[]
            }[]
            scene: string       // Scene type
        }
        favored: boolean
        deleted: boolean
        viewed: boolean
        createTime: number      // Creation timestamp
        updateTime: number      // Update timestamp
        viewTime: number        // View timestamp
        status_name: string     // Status name: "submitted"
        status_final: boolean   // Whether status is final
    }
    works: any[]                // Work items (empty initially)
    status: number              // Overall status
    message: string             // Status message
    error: string
    limitation: any | null      // Rate limiting info
    userPoints: {
        points: {
            orderId: string     // Order ID
            type: string        // Point type
            amount: number      // Point amount
            balance: number     // Remaining balance
            startTime: number   // Start timestamp
            endTime: number     // End timestamp
        }[]
        total: number           // Total points
    }
    userTickets: {
        ticket: {
            orderId: string     // Order ID
            type: string        // Ticket type
            packageType: string // Package type
            amount: number      // Ticket amount
            balance: number     // Remaining balance
            startTime: number   // Start timestamp
            endTime: number     // End timestamp
        }[]
    }
    editProject: any | null     // Edit project info
    status_name: string         // Status name
    status_final: boolean       // Whether status is final
}

Examples

curl "https://api.useapi.net/v1/kling/videos/add-sound" \
  -H "Accept: application/json" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer …" \
  -d '{
    "email": "[email protected]",
    "video": "https://s21-kling.klingai.com/....mp4",
    "replyUrl": "https://my.domain.com/webhook-endpoint-kling"
  }'

const token = "API token";
const email = "Previously configured account email";
const requestData = {
  email,
  video: "https://s21-kling.klingai.com/....mp4",
  replyUrl: "https://my.domain.com/webhook-endpoint-kling"
};
const response = await fetch("https://api.useapi.net/v1/kling/videos/add-sound", {
  method: "POST",
  headers: {
    "Content-Type": "application/json", 
    "Authorization": `Bearer ${token}`,
  },
  body: JSON.stringify(requestData)
});
const result = await response.json();
console.log("response", {response, result});

import requests
token = "API token"
email = "Previously configured account email"
request_data = {
    "email": email,
    "video": "https://s21-kling.klingai.com/....mp4",
    "replyUrl": "https://my.domain.com/webhook-endpoint-kling"
}
headers = {
    "Content-Type": "application/json",
    "Authorization": f"Bearer {token}"
}
response = requests.post("https://api.useapi.net/v1/kling/videos/add-sound", 
                        headers=headers, 
                        json=request_data)
print(response, response.json())