---
name: Step 3.5 Flash 2603
slug: step-3-5-flash-2603
type: LLM
providers:
  - stepfun
description: 'StepFun flash model for efficient multimodal reasoning, coding, and tool use'
tags:
  - open-source
  - llm
  - reasoning
  - tool-use
is_open_source: true
context_window: 256000
max_output: 256000
pricing:
  - image: 0
    input: 0.1
    output: 0.3
    provider: stepfun (Ver 2603)
release_date: '2026-04-02'
capabilities:
  audio: false
  vision: false
  tool_use: true
  citations: false
  reasoning: true
---
Step 3.5 Flash 2603 is a LLM model.
StepFun flash model for efficient multimodal reasoning, coding, and tool use