Step 3.7 Flash, the StepFun model in numbers

What you need to know

Released on May 29, 2026, Step 3.7 Flash is one of the 2 StepFun models tracked on this site. Its weights are published: you can download it and run it on your own servers, or use one of the 22 API providers that list it on models.dev. It has a reasoning mode: it can "think" before answering, which helps with multi-step problems but uses more tokens, and therefore more money. That makes it 5 months old as of October 22, 2026.

We file it under open-weight models (68 models in this category on the site).

Benchmark results

As of October 22, 2026, Epoch AI publishes no score for Step 3.7 Flash on our basket's benchmarks. To place it, rely on its specifications and price, then test it on your own cases.

Context and capabilities

Its context window reaches 256,000 tokens, roughly 384 pages of text at 500 words per page: enough for a long report or several contracts at once. A single answer can run to 256,000 tokens.

It accepts as input: text, image and video. Its knowledge stops at March 1, 2026: beyond that, it needs web search or your documents.

It can call tools (functions, APIs) and return structured JSON output, which makes it a possible foundation for an AI agent.

The weights are published on Hugging Face (stepfun-ai/Step-3.7-Flash). See also our list of open-source models.

Pricing and budget

Step 3.7 Flash costs $0.20 per million input tokens and $1.21 per million output tokens (developer's price, checked on October 22, 2026).

To put it in perspective: reading 20,000 tokens (about thirty pages) and writing 2,000 costs roughly $0.006; a thousand of those tasks, $6.46.

That is 1.2 times the median output price of open-weight models ($1).

Tokens read back from cache cost $0.04 per million, which helps an agent that keeps resending the same context.

To estimate your own budget, use the agent cost calculator.

When to choose it

Given its category, Step 3.7 Flash is mainly aimed at projects where you want control over your data or hosting, or want to adapt the model to your field.

Before adopting it, test it on your own examples: benchmarks measure standard tasks, not your job.

Alternatives

In the same category, the models closest to Step 3.7 Flash are:

• MiniMax-M3 (MiniMax, index 55.5)
• Muse Glimmer 30B (Meta, $1.2 per million output tokens)
• MiniMax-M2.7 (MiniMax, $1.2 per million output tokens)
• DeepSeek V3 0324 (DeepSeek, $1.1 per million output tokens)