Last refreshed 2026-05-27. Next refresh: weekly.
Why use StepAudio 2.5 ASR on StepFun?
StepFun offers StepAudio 2.5 ASR with competitive pricing. StepFun is a Chinese AI company providing API access to its Step series of large language and multimodal models.
Setup recipe
Docs fallbackUse the provider REST API or SDKCreate a provider API keymodel: stepaudio-2.5-asrstepaudio-2.5-asrRequest example
stepaudio-2.5-asr.Gotchas
- Use provider model ID "stepaudio-2.5-asr", not the LLMReference slug "step-audio-2-5-asr".
Capabilities
About StepAudio 2.5 ASR
StepAudio 2.5 ASR is StepFun's automatic speech recognition model. At 4B parameters, it introduces Multi-Token Prediction (MTP) technology to parallelly predict multiple tokens per decoding step, enabling transcription of 5 minutes of audio in approximately 1 second. Achieves 400% higher throughput and 60% lower latency compared to prior StepFun ASR systems while maintaining state-of-the-art accuracy. Supports Chinese and English; accepts PCM, OGG, MP3, and WAV formats. Available via the StepFun API (model: stepaudio-2.5-asr). Part of the unified StepAudio 2.5 architecture described in arXiv:2605.23463.
FAQ
What API model ID do I use for StepAudio 2.5 ASR on StepFun?
Use the model ID stepaudio-2.5-asr when calling StepFun's API.
Who created StepAudio 2.5 ASR?
StepAudio 2.5 ASR was created by StepFun as part of the StepAudio 2.5 model family.
Is StepAudio 2.5 ASR open source?
StepAudio 2.5 ASR is not open source; the seed data lists it as proprietary.