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stepfun

StepFun: Step 5 Preview

stepfun/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).

Context window: 1,048,576 tokens
Input: text, image, video
Output: text
Pricing: $1/M input tokens, $2.7/M output tokens

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