LLM Reference

Step 3.7 Flash

Released
2026-05-29
Last refreshed
2026-06-29
Status
Researched 45d ago
ProprietaryCommercial use: conditionalMultimodalCodingRAGAgentsLong contextVisionJSON / Tool use

Step 3.7 Flash is worth evaluating for coding, rag, and agents when its provider route and context window match the workload.

Use it for

  • Teams evaluating coding, rag, and agents
  • Workloads that can use a 256k context window
  • Buyers comparing 3 tracked provider routes

Do not use it for

  • Workloads where another current model has stronger sourced task evidence
Specifications
Family
Step
Released
2026-05-29
Context
256k
Parameters
198B (11B active)
Architecture
Mixture of Experts
Specialization
general
Openness
Proprietary
License
ProprietaryCommercial use: conditional
Weights
Not released
Code
Unknown
Training
Pretrained
Created by

One of China's leading AI 'Six Tigers'.

Shanghai, China
Founded 2023
Website
Pricing
Output / 1M
$1.15
Input / 1M
$0.200

Cheapest of 3 routes · OpenRouter

About

Step 3.7 Flash is StepFun's open-weights multimodal Mixture-of-Experts model for agentic coding, tool use, long-context reasoning, image understanding, and video understanding. It combines a 196B-parameter language backbone with a 1.8B-parameter vision encoder, activates about 11B parameters per token, supports a 256K-token context window, and exposes low, medium, and high reasoning levels for speed/depth tradeoffs. StepFun reports leading open-model results on ClawEval-1.1, SimpleVQA with Search, and SWE-bench Pro at launch. Weights are available on Hugging Face under Apache 2.0.

Step 3.7 Flash is a proprietary model in the Step family. The structured metadata tracks a 256k-token context window, multimodal input, reasoning, function calling, tool use, and structured outputs. This page tracks provider routes through StepFun, OpenRouter, and NVIDIA NIM, with the cheapest tracked route listed at $0.2 input and $1.15 output per 1M tokens. Headline tracked benchmarks include ClawEval-1.1 67.1, SimpleVQA with Search Tool 79.2, and V* with Python 95.3.

Top use-case fit: coding, agents, and build tasks

Coding

Q/$ C

1 relevant benchmark in the decision map.

RAG

Included by capability and metadata signals in the decision map.

Agents

Included by capability and metadata signals in the decision map.

Provider price ladder

Compare all 3

Compare API pricing across 3 providers for input and output tokens, batch, and cached reads when available.

ProviderInput / 1MOutput / 1MCacheRoute
OpenRouter$0.200$1.15-
Serverless
StepFun$0.200$1.15read $0.040
Serverless
NVIDIA NIM---
ProvisionedPartial

Available via routers & gateways(1)

Capabilities

VisionMultimodalReasoningFunction CallingTool UseStructured OutputsPrompt Caching

Benchmark peer barsfor Coding

Benchmark scores(14)

Scores are benchmark-specific and are direction-aware: the same numeric gap can mean very different outcomes across suites. Use the leaderboard context and this model's provider route to decide whether the winning margin is meaningful for your workload.
BenchmarkScoreVersionSource
ClawEval-1.167.11st among open models at releasehttps://static.stepfun.com/blog/step-3.7-flash/
SimpleVQA with Search Tool79.21st at release (GPT-5.5: 79.1)https://static.stepfun.com/blog/step-3.7-flash/
V* with Python95.32nd at release (Kimi K2.6: 96.9)https://huggingface.co/stepfun-ai/Step-3.7-Flash
SWE-bench Pro56.32nd at release (Claude Opus 4.7: 64.3, GPT-5.5: 58.6)https://static.stepfun.com/blog/step-3.7-flash/
Terminal-Bench 2.159.5Comparison: Step 3.5 Flash 53.37%, DeepSeek V4 Flash 62.0%, Gemini 3.5 Flash 76.2%, GPT-5.5 82.7%, Claude Opus 4.7 69.4%https://static.stepfun.com/blog/step-3.7-flash/
Toolathlon49.5https://huggingface.co/stepfun-ai/Step-3.7-Flash
Humanity's Last Exam47.2https://huggingface.co/stepfun-ai/Step-3.7-Flash
GDPval-AA45.8https://huggingface.co/stepfun-ai/Step-3.7-Flash
WorldVQA58.1Comparison: Kimi K2.6 55.98%https://static.stepfun.com/blog/step-3.7-flash/
HR-Bench 4K89.1Comparison: Kimi K2.6 91.25%https://static.stepfun.com/blog/step-3.7-flash/
Android Daily61.9Comparison: Gemini 3 Flash 63.21%https://static.stepfun.com/blog/step-3.7-flash/
DeepSearchQA92.8https://static.stepfun.com/blog/step-3.7-flash/
BrowseComp75.8From official StepFun blog post (accuracy%)https://static.stepfun.com/blog/step-3.7-flash/
ResearchRubrics71.7https://static.stepfun.com/blog/step-3.7-flash/

Migration checks

No linked migration route is available for this model yet.

API versions

step-3.7-flash

Compare Step 3.7 Flash with other models

Frequently asked questions

What is the context window of Step 3.7 Flash?

Step 3.7 Flash has a context window of 256k tokens.

How much does Step 3.7 Flash cost?

Step 3.7 Flash pricing ranges from $0.20/1M to $0.2/1M input tokens depending on the provider.

When was Step 3.7 Flash released?

Step 3.7 Flash was released on 2026-05-29.

Which providers offer Step 3.7 Flash?

Step 3.7 Flash is available from 3 providers: StepFun, OpenRouter, NVIDIA NIM.

What benchmarks has Step 3.7 Flash been tested on?

Step 3.7 Flash has been evaluated on 14 benchmarks, including ClawEval-1.1, SimpleVQA with Search Tool, V* with Python, SWE-bench Pro, Terminal-Bench 2.1.