Step 3.5 Flash by NanoGPT — Specs, Pricing & Capabilities | whichllm

Model ID stepfun-ai/step-3.5-flash

Provider NanoGPT

Family step

Status -

Knowledge Cutoff -

Release Date 2026-02-02

Input Modalities text

Output Modalities text

Context Window 256000

Input Limit 256000

Output Limit 256000

Tool Calling No

Reasoning Yes

Structured Output No

Temperature Control -

Open Weights No

Input Cost / 1M tokens $0.20

Output Cost / 1M tokens $0.50

Reasoning Cost / 1M tokens -

Cache Read Cost / 1M tokens -

Cache Write Cost / 1M tokens -