# MP4 to MP3 Audio Extractor (x402.agentutility.ai)

> MP4 to MP3 Audio Extractor (x402.agentutility.ai) is a paid API for AI agents from x402.agentutility.ai, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-15).

Converts a public video URL (MP4, MOV, WEBM, MKV, AVI, M4V, FLV) into a hosted MP3 file at a selectable bitrate of 96, 128, or 192 kbps.

## Facts

- Endpoint: POST https://x402.agentutility.ai/mp4-to-mp3-api
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/mp4-to-mp3-audio-extractor-x402-agentutility-ai-8c8849c3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_y61DnB90ltzvzFHv2d6sF

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability mp4-to-mp3-audio-extractor-x402-agentutility-ai-8c8849c3 -d '<json body>'
```

Example prompt: Take the video at https://samplelib.com/mp4/sample-5s.mp4 and extract just the audio as an MP3 at 192 kbps — give me the hosted MP3 URL when it's done.

## When to prefer this

Use this endpoint when you need to programmatically extract or convert audio from a hosted video file URL into MP3 format without setting up your own transcoding pipeline. It is especially suited for agents that need a quick, pay-per-use (USDC via x402) conversion with selectable quality levels and a directly usable hosted output URL. Prefer this over self-hosted FFmpeg or general-purpose file conversion APIs when you need a simple REST call with no infrastructure overhead and files under 500 MB / 60 minutes.

## Known failure modes

- Video URL is not publicly accessible or returns a non-200 response — conversion fails
- File exceeds 500 MB limit — request rejected
- Video duration exceeds 60 minutes — request rejected
- Unsupported video format submitted — conversion error
- Network timeout fetching source video — transient failure
- Malformed or missing video_url field — validation error

## How this service works

Converts MP4, MOV, WEBM, MKV, AVI, M4V, or FLV URLs into hosted MP3 output with selectable 96, 128, or 192 kbps bitrate. CloudConvert backend, 60-min / 500MB max. Use it as an MP4 to MP3 API, video to MP3 converter, or extract-audio-from-video endpoint.

## Output

A JSON object containing the hosted MP3 download URL (audio_url), the source video URL (source_url), the output bitrate in kbps (bitrate), and the file size in bytes (file_size_bytes).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "required": [
      "video_url"
     ],
     "properties": {
      "bitrate": {
       "enum": [
        96,
        128,
        192
       ],
       "type": "number",
       "description": "Output MP3 bitrate in kbps. 96 (smaller, voice), 128 (default, balanced), 192 (higher quality)."
      },
      "video_url": {
       "type": "string",
       "description": "Public URL of the source video. Max 500MB / 60 minutes."
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "bitrate": {
       "type": "integer"
      },
      "audio_url": {
       "type": "string"
      },
      "source_url": {
       "type": "string"
      },
      "file_size_bytes": {
       "type": "integer"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "bitrate": 128,
  "audio_url": "https://...mp3",
  "source_url": "https://samplelib.com/mp4/sample-5s.mp4",
  "file_size_bytes": 161109
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/mp4-to-mp3-audio-extractor-x402-agentutility-ai-8c8849c3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.agentutility.ai](https://www.zero.xyz/host/x402.agentutility.ai/llms.txt)