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Step 5 Preview — Free AI Chat on Rewind.ai
Chat with Step 5 Preview for free — no signup, no credit card. StepFun's Step 5 Preview runs in your browser on Rewind.ai, with pay-as-you-go tokens and full API access.
What is Step 5 Preview?
Step 5 Preview is StepFun's flagship model for agentic work, built on a sparse Mixture-of-Experts architecture (27B active / 600B total parameters). It performs strongly in software engineering and professional.
How does Step 5 Preview work?
Type your message in the box above and Step 5 Preview replies instantly — no setup required. Your chat history is saved locally in your browser; sign up free to sync it across devices and get an extra 10,000 tokens. You can switch between Step 5 Preview and other models at any time from the picker at the top.
Is Step 5 Preview free?
Step 5 Preview is pay-as-you-go at $1.00/M input tokens, but you can use it without paying: every visitor gets 2,500 free tokens a day with no sign up, and a free account raises that to 5,000.