Step 3.5 Flash
by Stepfun
Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parame
Models
Step 3.5 Flash
Added 10 July 2026
Overview
Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parameters per token....
How to use / API access
Call via OpenRouter with model id `stepfun/step-3.5-flash`.
- openrouter ·
stepfun/step-3.5-flashDocs
OpenRouter id: stepfun/step-3.5-flash
Benchmarks
- Intelligence Index (artificial-analysis): 17 index
Notes
Step 3.5 Flash is listed in the EDNA Models directory from the OpenRouter catalogue.
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