Step 5 Preview
StepFun's Step 5 preview model, listed on API aggregators in October 2026
Paid
Reasoning
131072
context tokens
Undisclosed
parameters
Proprietary
license
Oct 2026
released
StepFun’s Step 5 Preview appeared on API aggregators in October 2026 with a 128K context window. StepFun has not published much detail, and the exact release date is unconfirmed.
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