StepAudio 3 ASR Max vs StepAudio 2.5 ASR

StepAudio 3 ASR Max vs StepAudio 2.5 ASR at a glance

StepAudio 3 ASR Max and StepAudio 2.5 ASR are both StepFun models in the Transcription category, available through the EmpirioLabs API.

Key differences

• StepAudio 3 ASR Max is the newer release (Aug 31, 2026); StepAudio 2.5 ASR was released on Apr 24, 2026.
• Capabilities listed only for StepAudio 3 ASR Max: multilingual.
• Capabilities listed only for StepAudio 2.5 ASR: streaming asr, timestamps.
• StepAudio 2.5 ASR lists the lower rate for Transcription (per hour of audio).

StepAudio 3 ASR Max vs StepAudio 2.5 ASR: specs

StepAudio 3 ASR Max vs StepAudio 2.5 ASR: API pricing

Live rates from the EmpirioLabs catalog for both models. Each rate card always matches what the API charges.

StepAudio 3 ASR Max vs StepAudio 2.5 ASR: API parameters

Request parameters each model lists on EmpirioLabs, with the allowed values or range where one applies. A dash marks a parameter the model does not list.

StepAudio 3 ASR Max vs StepAudio 2.5 ASR: limits and notes

StepAudio 3 ASR Max

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 2.5 ASR

Supports wav, mp3, ogg, and pcm input. PCM requests should include codec, sample rate, bit depth, and channel count. Recognition language supports Chinese and English. Timestamp output is available through enable_timestamp.

How to call StepAudio 3 ASR Max and StepAudio 2.5 ASR

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. Both models are called through the same endpoint. Set model to stepaudio-3-asr-max or stepaudio-2-5-asr. 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"
  }'

StepAudio 3 ASR Max vs StepAudio 2.5 ASR: common questions

What is the difference between StepAudio 3 ASR Max and StepAudio 2.5 ASR?

StepAudio 3 ASR Max is the newer release (Aug 31, 2026); StepAudio 2.5 ASR was released on Apr 24, 2026. Capabilities listed only for StepAudio 3 ASR Max: multilingual. Capabilities listed only for StepAudio 2.5 ASR: streaming asr, timestamps. The specs, rate cards, and parameters on this page come from the live EmpirioLabs catalog.

Which is newer, StepAudio 3 ASR Max or StepAudio 2.5 ASR?

StepAudio 3 ASR Max is the newer release (Aug 31, 2026); StepAudio 2.5 ASR was released on Apr 24, 2026.

Which has the lower rate, StepAudio 3 ASR Max or StepAudio 2.5 ASR?

StepAudio 2.5 ASR lists the lower rate for Transcription (per hour of audio). Both live rate cards are on this page and always match what the API charges.

Can I switch between StepAudio 3 ASR Max and StepAudio 2.5 ASR without rebuilding my integration?

Yes. Both models use POST /v1/audio/transcriptions with the same EmpirioLabs API key, so most integrations switch by changing the model value. Check the parameters table on this page first if you rely on a model-specific parameter.

Can I try StepAudio 3 ASR Max and StepAudio 2.5 ASR in the browser before integrating?

Yes. Open each model in the EmpirioLabs playground and run the same prompt on both, with the parameters the API exposes.