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Step 3.5 Flash

Name: Step 3.5 Flash
Author: Stepfun

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

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Models

Step 3.5 Flash

Added 10 July 2026

#stepfun

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-flash Docs

OpenRouter id: stepfun/step-3.5-flash

Benchmarks

Intelligence Index (artificial-analysis) : 25.5 index

Notes

Step 3.5 Flash is listed in the EDNA Models directory from the OpenRouter catalogue.

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