Step TTS 2 API
About
Step TTS 2 is a high-performance LLM available via the StepFun (Global) API, ideal for scalable text generation and natural language processing. This model delivers available completely free of charge. Access Step TTS 2 via the StepFun (Global) API with reliable low-latency inference.
Capabilities
Input Modalities
text
Output Modalities
audio
Reasoning
No
Structured Output
No
Tool Use
No
WeightsClosed
Temperature
Fixed
Attachment
Not Supported
Limits
Context Window
N/A
Tokens
Input Limit
N/A
Tokens
Max Output
N/A
Tokens
Pricing
Standard (per 1M tokens)
Input
Free
Output
Free
Frequently Asked Questions
Step TTS 2 by StepFun (Global) costs Free per 1M input tokens and Free per 1M output tokens.
Model Details
API Integration
NPM Package
@ai-sdk/openai-compatible
Environment Variables
STEPFUN_API_KEY
API Base URL
https://api.stepfun.ai/v1