FAST & FRUGAL · StepFun

Step 3.5 Flash

Step 3.5 Flash is a reasoning, tool-using model from StepFun in the StepFun family, living in Silvergrass Fields (fast & frugal). It reads text and writes text, with a 262K-token context window and up to 66K tokens of output. On OpenRouter it costs $0.100 per million input tokens and $0.300 per million output tokens.

See Step 3.5 Flash in 3D Open in the Worktable View on OpenRouter

Specifications

Provider: StepFun
Family: StepFun
Province: Silvergrass Fields
Context window: 262K tokens
Maximum output: 66K tokens
Input / 1M tokens: $0.100
Output / 1M tokens: $0.300
Accepts: text
Produces: text
Reasoning: Yes
Tool use: Yes
Added to OpenRouter: 2026-01-29
Model ID: stepfun/step-3.5-flash
Price history: —All recorded prices

From the 2026-10-24 catalog snapshot. Prices are US dollars per million tokens.

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