Voxtral Mini Transcribe - Benchmarks & Performance - OpenTranscription

Voxtral Mini Transcribe

Name: Voxtral Mini Transcribe
Author: Mistral (Voxtral)

Batch

Mistral Voxtral Mini Transcribe — EU-hosted batch transcription with speaker diarization, segment timestamps, and custom vocabulary (context bias). Strong accuracy at very low cost; handles recordings up to 3 hours.

Transcribe with this model Compare in playground

8 languages · benchmarked

Overall Score

79.3

Word Error Rate

15.50%

Character Error Rate

11.10%

Match Error Rate

14.68%

Word Info Lost

19.01%

Avg Latency

2.3s

Benchmarks Run

Cost vs. accuracy

overall WER · 31 models

field · 31 models

lower-left is better

Performance by category

8 categories

WER

lower is better

Legal

3.8%

Technical

6.7%

Medical

7.3%

Finance

9.3%

Conversational

11.7%

General

13.3%

Code-Switching

23.5%

Noisy Environment

38.5%

Category	WER	CER	MER	WIL	Latency	Benchmarks
Code-Switching	23.50%	15.63%	23.04%	30.87%	3.3s	2
Conversational	11.68%	6.92%	11.65%	14.24%	2.9s	2
Finance	9.32%	3.37%	9.20%	14.58%	2.6s	2
General	13.34%	9.54%	13.32%	17.05%	2.2s	14
Legal	3.78%	1.97%	3.74%	4.39%	2.5s	2
Medical	7.31%	4.84%	7.31%	8.61%	2.5s	2
Noisy Environment	38.47%	31.82%	32.76%	42.33%	1.5s	4
Technical	6.65%	3.35%	6.58%	8.41%	2.8s	2

Performance by accent

5 accents

Accent	WER	Benchmarks
African	29.23%	1
Australian	9.38%	1
Indian	12.70%	1
British	2.99%	1
American	0.00%	1

Pricing

pay per second

Rate

$0.003

/min

Per-second billing. Bring your own provider key and pay your provider directly — a 5% routing fee applies (first 100 min/mo free).

Set up BYOK

Cost estimator

1 hour

$0.18

10 hours

$1.80

100 hours

$18

1,000 hours

$180

Billed per second of audio processed.

API & usage

POST /api/v1/transcriptions

Model ID

mistral/voxtral-mini-transcribe

Get an API key

Authenticate every request with your secret API key as a Bearer token. Issue a key from your dashboard.

Quickstart

Upload your audio, create a job with this model, then poll the job or set a webhook_url to be notified when it completes.

# 1. Request a signed upload URL
curl https://opentranscription.io/api/v1/uploads \
  -H "Authorization: Bearer $OT_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "file_name": "interview.mp3", "file_size": 3456789, "mime_type": "audio/mpeg" }'
# → { "upload_url": "...", "file_path": "...", "expires_at": "..." }

# 2. Upload the audio bytes to the signed URL
curl -X PUT "$UPLOAD_URL" --upload-file interview.mp3

# 3. Create the transcription job
curl https://opentranscription.io/api/v1/transcriptions \
  -H "Authorization: Bearer $OT_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "file_path": "$FILE_PATH",
    "model": "mistral/voxtral-mini-transcribe",
    "language": "en",
    "diarization": true,
    "webhook_url": "https://your-app.com/webhooks/ot"
  }'
# → we POST a signed event to your webhook_url when the job finishes — no polling required

Key parameters

file_path

string

required

Storage path returned by the upload step.

model

string

required

The model to run this job on.

language

string

ISO 639-1 language code. Omit to auto-detect.

diarization

boolean

Label speakers (A, B, …) in the output.

webhook_url

string

HTTPS URL notified with the result when the job completes. Delivered events are signed (X-OT-Signature).

Response

A completed job returns the transcript in the OpenTranscription Unified Schema (OTUS).

{
  "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "status": "completed",
  "transcript": {
    "text": "Welcome to the meeting, everyone.",
    "language": "en",
    "confidence": 0.97,
    "segments": [
      {
        "id": 0,
        "start": 0,
        "end": 3.5,
        "text": "Welcome to the meeting, everyone.",
        "speaker": "A"
      }
    ]
  }
}

Webhooks — skip polling

We POST a signed event to your webhook_url when a job completes or fails; verify the X-OT-Signature (HMAC-SHA256, reject if older than 300 s) and dedupe on the event id, then fetch the full transcript via GET /api/v1/transcriptions/{id}.

# We POST a signed event to your webhook_url when a job finishes.
# Headers:
#   X-OT-Signature: t=1736937042,v1=5257a869e7eceb6c6c2c2a1b4d6e9f8c2a1b4d6e9f8c2a1b4d6e9f8c2a1b4d6e
#   X-OT-Event-Id: evt_9f8c2a1b4d6e
#   X-OT-Event-Type: transcription.completed
#
# Body (thin event — fetch the transcript with GET /transcriptions/{data.id}):
{
  "id": "evt_9f8c2a1b4d6e",
  "event": "transcription.completed",
  "created": "2025-01-15T10:30:42.000Z",
  "data": {
    "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
    "status": "completed",
    "error_code": null
  }
}
#
# Verify: HMAC-SHA256 over "<t>.<raw_body>" with your signing secret,
# constant-time compare against any v1, and reject if |now - t| > 300s.

Rate-limited per tier — see the X-RateLimit-* response headers.

Full API reference

Similar models

from the same field

More accurate

Chirp 3

Google Cloud

14.05% WER

$0.0107/min

Compare →

Cheaper

Whisper Large V3 Turbo

Groq

18.39% WER

$0.0007/min

Compare →

Supported Languages

EnglishSpanishFrenchGermanItalianPortugueseDutchHindi

Supported Formats

mp3wavflacm4aoggwebm

Features

Auto-detectDiarizationCustom Vocabulary

Voxtral Mini Transcribe

Cost vs. accuracy

Performance by category

Performance by accent

Pricing

API & usage

Similar models

About Voxtral Mini Transcribe