# Audio Transcriber – Fast Whisper (tiny/base/small) from URL (`datvanu/audio-transcriber`) Actor

Fast, affordable Whisper transcription from direct audio/video URLs (CPU int8). Default small – solid for English & clear speech (DE FLEURS WER ≈10.8%, 60 clips). tiny/base available. Failed files never charged. No YouTube scraping.

- **URL**: https://apify.com/datvanu/audio-transcriber.md
- **Developed by:** [Kilian Schieri](https://apify.com/datvanu) (community)
- **Categories:** AI, Videos, Developer tools
- **Security:** Limited permissions
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $12.00 / 1,000 audio minute (small)s

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

An Actor is a serverless cloud program that runs on the Apify platform. It has two run modes.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.

Apify vocabulary and the platform model are defined once, in the agent quickstart at https://apify.com/agents.md.

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.

Do not guess an integration path. Every one of them is in the agent quickstart at https://apify.com/agents.md: the Apify MCP server, Agent Skills with the Apify CLI, the JavaScript and Python clients, the REST API, and the account-free path for an agent with no human to sign in. It also carries the rule on stating cost before the first paid run.

For examples already wired to this Actor's own input schema, see the [API](#api) section below.

Each client library has reference documentation the quickstart does not restate: [JavaScript/TypeScript](https://docs.apify.com/api/client/js/docs.md) (`npm install apify-client`) and [Python](https://docs.apify.com/api/client/python/docs.md) (`pip install apify-client`).

# README

## Audio Transcriber – Fast Whisper from URL

Fast, **affordable** transcription of **audio or video files from direct URLs** with [faster-whisper](https://github.com/SYSTRAN/faster-whisper) on **CPU (int8)**. Choose **tiny**, **base** or **small** (default). Returns plain text, timestamped segments, detected language and duration. The default **small** model is baked into the image for faster cold starts.

**Best for:** English and clear, studio-like speech. **Measured German WER** (own bench, 2026-11-05): small ≈ **10.8 %** on FLEURS `de_de` (60 clips, 1375 words); ≈ **13.6 %** on MLS German (60 clips). For higher DE accuracy (~4.7 % FLEURS) use [`datvanu/audio-transcriber-pro`](https://apify.com/datvanu/audio-transcriber-pro).

**No YouTube / TikTok / Instagram page URLs** – pass a direct file link (mp3, wav, ogg, m4a, mp4, webm, …). Failed files are `ERROR` rows and **never charged**.

### Input

| Field | Default | Notes |
|---|---|---|
| `urls` | – | Direct http(s) links, max 50 per run |
| `model` | `small` | `tiny` / `base` / `small` |
| `language` | auto | ISO-639-1, e.g. `en`, `de` |
| `task` | `transcribe` | or `translate` (to English) |
| `includeSegments` | `true` | Timestamped `segments[]` |
| `beamSize` | `5` | 1 = fastest; up to 5 |
| `vadFilter` | `true` | Skip long silence |
| `maxFileBytes` | 200 MB | Oversized downloads → ERROR, not charged |

Prefill: short public-domain Aesop fable (~46 s) from LibriVox / Internet Archive.

### Output (one dataset item per URL)

`status` (`OK` / `ERROR`), `url`, `model`, `task`, `language`, `languageProbability`, `durationSecs`, `audioMinutes` (started minutes, ceil), `text`, `segments[]` (`start`, `end`, `text`), `error`, `transcribedAt`.

Key-value record `RUN_SUMMARY` holds counts and charged minutes.

### Pricing (PPE)

| Event | When |
|---|---|
| `audio-minute-tiny` | started minute with `model=tiny` |
| `audio-minute-base` | started minute with `model=base` |
| `audio-minute-small` | started minute with `model=small` |
| `apify-actor-start` | Actor start (platform standard) |

Minutes are rounded up per file. Failed files are never charged. Remove synthetic `apify-default-dataset-item` before publish.

### Memory

Default **4096 MB**. `tiny` often runs at 1024 MB; `small` is safer at 2048–4096 MB.

### Licence / source notes

- Engine: faster-whisper / CTranslate2, MIT.
- Prefill sample: LibriVox recording of Aesop’s Fables (public domain), hosted on archive.org.
- You are responsible for having the right to transcribe the files you submit (copyright, privacy).

# Actor input Schema

## `urls` (type: `array`):

Direct http(s) links to audio or video files (mp3, wav, ogg, m4a, mp4, webm, …). No YouTube/TikTok/Instagram page URLs – pass a direct file link. Max 50 URLs per run. Prefill is a short public-domain LibriVox Aesop clip (~46 s) for cheap Store tests.

## `model` (type: `string`):

faster-whisper model size (CPU int8). Default small: solid for English and clear speech (measured DE WER ≈10.8% on FLEURS de_de, 60 clips, beam 5 + VAD). Use base/tiny for cheaper drafts. For higher DE accuracy see datvanu/audio-transcriber-pro.

## `language` (type: `string`):

ISO-639-1 code to force (e.g. en, de, fr). Leave empty to auto-detect. Detection runs on the beginning of the file.

## `task` (type: `string`):

Whisper task. translate always produces English text.

## `includeSegments` (type: `boolean`):

When true, each result includes a segments\[] array with start/end (seconds) and text.

## `beamSize` (type: `integer`):

Decoding beam size. Default 5 (quality). Use 1 for fastest/cheapest runs.

## `vadFilter` (type: `boolean`):

Silero VAD drops long silence before decoding – usually faster and cheaper on podcasts with pauses.

## `maxFileBytes` (type: `integer`):

Refuse downloads larger than this (default 200 MB). Failed / oversized files are not charged.

## Actor input object example

```json
{
  "urls": [
    "https://archive.org/download/aesop_fables_volume_one_librivox/fables_01_01_aesop_64kb.mp3"
  ],
  "model": "small",
  "language": "en",
  "task": "transcribe",
  "includeSegments": false,
  "beamSize": 5,
  "vadFilter": true,
  "maxFileBytes": 209715200
}
```

# Actor output Schema

## `results` (type: `string`):

All items of the default dataset (JSON). Add ?format=csv or xlsx for other formats.

## `runSummary` (type: `string`):

Counts, models used and charged audio-minutes of this run (key RUN_SUMMARY).

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {
    "urls": [
        "https://archive.org/download/aesop_fables_volume_one_librivox/fables_01_01_aesop_64kb.mp3"
    ],
    "model": "small",
    "language": "en",
    "includeSegments": false,
    "beamSize": 5
};

// Run the Actor and wait for it to finish
const run = await client.actor("datvanu/audio-transcriber").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = {
    "urls": ["https://archive.org/download/aesop_fables_volume_one_librivox/fables_01_01_aesop_64kb.mp3"],
    "model": "small",
    "language": "en",
    "includeSegments": False,
    "beamSize": 5,
}

# Run the Actor and wait for it to finish
run = client.actor("datvanu/audio-transcriber").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{
  "urls": [
    "https://archive.org/download/aesop_fables_volume_one_librivox/fables_01_01_aesop_64kb.mp3"
  ],
  "model": "small",
  "language": "en",
  "includeSegments": false,
  "beamSize": 5
}' |
apify call datvanu/audio-transcriber --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,datvanu/audio-transcriber"
        }
    }
}
```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/0KofigHzQOw5T2js8/builds/TcEoaEGXRRkngATOd/openapi.json