StepAudio 3 ASR Max API

About StepAudio 3 ASR Max

Context-aware transcription for proper nouns, technical terms, dialects, and difficult audio including whispers, fast speech, and singing.

EmpirioLabs exposes the standard /v1/audio/transcriptions endpoint and returns the final transcript in the normal transcription response format.

Also known as StepFun StepAudio 3 ASR Max

StepAudio 3 ASR Max specs

Model ID

stepaudio-3-asr-max

Author

StepFun

Category

Transcription

Released

Aug 31, 2026

Input

Audio

Output

Text

Region

International

Endpoints

POST/v1/audio/transcriptions

Alternate model IDs

stepfun/stepaudio-3-asr-max

StepAudio 3 ASR Max API pricing

Live pay-as-you-go rates from the EmpirioLabs catalog. You are billed only for what you use, with no monthly minimum.

How to call the StepAudio 3 ASR Max API

StepAudio 3 ASR Max runs through POST /v1/audio/transcriptions. The request returns a job_id right away; poll GET /v1/jobs/{job_id} until the job completes and read the output URLs from the result. Get an API key from the EmpirioLabs dashboard.

curl https://api.empiriolabs.ai/v1/audio/transcriptions \
  -H "Authorization: Bearer $EMPIRIOLABS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "stepaudio-3-asr-max",
    "audio_url": "https://example.com/meeting-recording.mp3"
  }'

curl https://api.empiriolabs.ai/v1/jobs/JOB_ID \
  -H "Authorization: Bearer $EMPIRIOLABS_API_KEY"

import requests

response = requests.post(
    "https://api.empiriolabs.ai/v1/audio/transcriptions",
    headers={"Authorization": "Bearer YOUR_EMPIRIOLABS_API_KEY"},
    json={
        "model": "stepaudio-3-asr-max",
        "audio_url": "https://example.com/meeting-recording.mp3",
    },
)
job = response.json()

# Generation runs as an async job. Poll until it completes.
import time
while True:
    status = requests.get(
        f"https://api.empiriolabs.ai/v1/jobs/{job['job_id']}",
        headers={"Authorization": "Bearer YOUR_EMPIRIOLABS_API_KEY"},
    ).json()
    if status.get("status") in ("completed", "failed"):
        print(status)
        break
    time.sleep(5)

StepAudio 3 ASR Max API parameters

Request parameters supported by the StepAudio 3 ASR Max API on EmpirioLabs. Defaults apply when a field is omitted.

Good to know

Supports wav, mp3, ogg, m4a, and pcm input. PCM requests should include codec, sample rate, bit depth, and channel count. The language is detected automatically and cannot be set; Chinese, English, Japanese, Korean, French, and Spanish are recognized, with languages other than Chinese and English in preview. Inverse text normalization is on by default and can be turned off with enable_itn. Hotwords and word timestamps are not available on this model. Audio is billed by its measured duration, with a one second minimum.

StepAudio 3 ASR Max API: common questions

How much does the StepAudio 3 ASR Max API cost?

On EmpirioLabs, StepAudio 3 ASR Max is billed pay as you go: Transcription $0.24 per hour of audio. The live rate card on this page always matches what the API charges.

Which endpoint does StepAudio 3 ASR Max use?

StepAudio 3 ASR Max is served through POST /v1/audio/transcriptions on api.empiriolabs.ai with standard bearer-token authentication.

Can I try StepAudio 3 ASR Max in the browser before integrating?

Yes. The EmpirioLabs playground runs StepAudio 3 ASR Max in the browser with the same parameters the API exposes, so you can test prompts before writing code.

How do I get a StepAudio 3 ASR Max API key?

Create an EmpirioLabs account, then generate a key under API Keys in the dashboard. Billing is pay-as-you-go credits, so you only pay for the requests you make.