Step 3.7 Flash
Key facts · verified Oct 27, 2026
Step 3.7 Flash is a StepFun model released on 29 May 2026. Its API price is $0.20 per million input tokens and $1.15 per million output tokens ($0.04 cached input). Its context window is 256K tokens. It is not yet ranked on LMArena's text leaderboard. Source: platform.stepfun.ai.
StepFun’s Step 3.7 Flash, released on 29 May 2026: a sparse mixture-of-experts model with 198 billion total and 11 billion active parameters, a 256K-token context window and native image and video understanding, built for agent and coding work. It offers three reasoning-effort levels and tool calling. The StepFun API charges $0.20 per million input tokens and $1.15 per million output tokens, and the weights are under Apache 2.0. On LMArena’s text leaderboard it has no LMArena rating.
$0.20 / $1.15 per million tokens
256K tokens
Not rated
Not ranked
Key Features
Full Specifications
$0.20 / $1.15 per million tokens | |
|---|---|
| Identity | |
| Developer | StepFun |
| Released | May 2026 |
| Licence | Apache 2.0 (open weights) |
| Self-hostable | Yes — stepfun-ai/Step-3.7-Flash on Hugging Face |
| Cost | |
| Blended $/1M tokensinput × 0.75 + output × 0.25 | $0.438 / 1M tokens |
| Input price | $0.200 / 1M tokens |
| Output price | $1.150 / 1M tokens |
| Cached input | $0.04 / 1M tokens |
| Capacity | |
| Context window | 256K tokens |
| Capability | |
| Vision in | Yes — images and video |
| Function calling | Yes |
| Extended reasoning | Yes — three reasoning-effort levels |
| Access | |
| API | Yes — StepFun Open Platform (step-3.7-flash) |