Takes 2 to 10 audio or video files (each up to 24 MB, together up to 60 minutes)
Takes 2 to 10 audio or video files (each up to 24 MB, together up to 60 minutes) and joins their audio in the given order. Between parts either a pause of chosen length or a crossfade is placed; optionally every part is brought to a common loudness first so that no part is suddenly louder. The start time of every part in the joined file is measured and returned, ready for chapter marks. Output as MP3, Opus, WAV or FLAC inline, max 8 MB. Runs locally with ffmpeg; nothing leaves this machine.
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://medien.halowerk.com/v1/audio-concat
| Category | Image and media |
|---|---|
| Provider host | medien.halowerk.com |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-31 | valid payment request | 402 | $0.004 | 1034 ms |
Example input (from the provider)
{
"body": {
"files": [
{
"label": "Teil 1",
"source": {
"url": "https://static.deepgram.com/examples/Bueller-Life-moves-pretty-fast.wav"
}
},
{
"label": "Teil 2",
"source": {
"url": "https://medien.halowerk.com/beispiel/notiz.mp3"
}
}
],
"gap_seconds": 1
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"additionalProperties": false,
"properties": {
"crossfade_seconds": {
"default": 0,
"description": "If > 0, parts overlap by this much instead of a gap.",
"maximum": 5,
"minimum": 0,
"type": "number"
},
"files": {
"items": {
"additionalProperties": false,
"properties": {
"label": {
"maxLength": 80,
"type": "string"
},
"source": {
"additionalProperties": false,
"properties": {
"content_base64": {
"maxLength": 5000000,
"type": "string"
},
"filename": {
"maxLength": 260,
"type": "string"
},
"url": {
"maxLength": 2048,
"type": "string"
}
},
"type": "object"
}
},
"required": [
"source"
],
"type": "object"
},
"maxItems": 10,
"minItems": 2,
"type": "array"
},
"gap_seconds": {
"default": 0.5,
"maximum": 10,
"minimum": 0,
"type": "number"
},
"match_loudness": {
"default": true,
"type": "boolean"
},
"output_format": {
"default": "mp3",
"enum": [
"opus",
"mp3",
"wav",
"flac"
],
"type": "string"
}
},
"required": [
"files"
],
"type": "object"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}