Using StepAudio 2.5 ASR on StepFun

Quick Start

1. 1
   Create an account at StepFun and generate an API key.
2. 2
   Use the StepFun SDK or REST API to call stepaudio-2.5-asr — see the documentation for request format.

Code Examples

About StepFun

StepFun is a Chinese AI company providing API access to its Step series of large language and multimodal models.

Pricing on StepFun

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.