Step 3.7 Flash
stepfun/step-3.7-flash-20260528
StepFun: Step 3.7 Flash is a model from stepfun that accepts text, image, and video inputs and generates text output. It supports tools and reasoning, provides open weights, and offers a context length of 262,144 tokens. The pricing is $0.20 per million input tokens and $1.15 per million output tokens.
- tool use
- structured outputs
- reasoning
- open-weight
At a glance
Specifications
What the API gives you
- Context window
- 262K tokens
- Max output
- 230K tokens
- Input price
- $0.20 / 1M tokens
- Output price
- $1.15 / 1M tokens
- Cache read
- $0.040 / 1M tokens
- Modalities
- text, image, video → text
- Knowledge cutoff
- —
- Released
- May 28, 2026
Measured evidence
Public benchmark record
- Design Arena Coding
- 1182 Elo2026-10-20
- Design Arena UI
- 1181 Elo2026-10-20
- Design Arena Website
- 1196 Elo2026-10-20
LMArena data licensed CC-BY-4.0. Aider (Apache-2.0) and SWE-bench (MIT) are open. Design Arena uses blind human preference.
Open-weight model on Hugging Face.
Task evidence
How broad is the support?
Each status is exact to this model version and the selected task. Official release claims remain provisional.
- Best LLM for Frontend & UIProvisional evidence
55% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from LiveBench Coding or LMArena WebDev. 6 of 6 configured evaluation feeds currently have results.
- Best LLM for CodingProvisional evidence
16% of intended weighted task evidence across 1 independent source; broader independent confirmation is still missing from Aider Polyglot or LiveBench Coding. 7 of 7 configured evaluation feeds currently have results.
Recommendation coverage
Where this model appears
Not currently included in a published recommendation. The task evidence panel above says exactly what is confirmed and what is still missing.
Catalog data via OpenRouter and models.dev. Last checked within the past 6 hours.