SnapOtter/apps/docs/tools/video/video-loudnorm.md

---
description: Normalize video audio volume to broadcast standard.
---

# Normalize Video Audio {#normalize-audio}

Normalize video audio volume to the EBU R128 broadcast loudness standard.

## API Endpoint {#api-endpoint}

`POST /api/v1/tools/video/video-loudnorm`

Accepts multipart form data with a video file. This tool has no configurable settings.

## Parameters {#parameters}

This tool has no parameters. It applies EBU R128 loudness normalization to the audio track.

## Example Request {#example-request}

```bash
curl -X POST http://localhost:1349/api/v1/tools/video/video-loudnorm \
  -H "Authorization: Bearer si_your-api-key" \
  -F "file=@clip.mp4"
```

## Example Response {#example-response}

```json
{
  "jobId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "downloadUrl": "/api/v1/download/a1b2c3d4-e5f6-7890-abcd-ef1234567890/clip.mp4",
  "originalSize": 12500000,
  "processedSize": 12500000
}
```

## Notes {#notes}

- Uses FFmpeg's `loudnorm` filter targeting -16 LUFS integrated loudness with -1.5 dBTP true peak and 11 LU loudness range (EBU R128 broadcast standard).
- The source audio sample rate is preserved in the output.
- If the video has no audio track, the request returns a 400 error.