StepFun: Step 3.5 Flash
stepfun/step-3.5-flash
Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parameters per token....
Source: OpenRouter (live)
- Input
- $0.100
- USD per 1M tokens
- Output
- $0.300
- USD per 1M tokens
- Blended
- $0.150
- 75% in / 25% out
- Context
- 262K
- tokens
- Max output
- 66K
- tokens
- Modality
- text->text
Prices as listed on OpenRouter, refreshed every five minutes. Provider-direct prices may differ. Convert to your currency on the AI Tracker.
Capabilities
Declared on the listing
- Tool / function calling Declared
- Reasoning controls Declared
- Structured output Not declared
- InputText
- OutputText
Capabilities are read from the provider listing. “Not declared” means the listing does not advertise the feature, not that it is absent.
Why it costs this
Pricing context
- 81% below median
- Cheap input
- Cheap output
- Market median blended price is $0.800/M across 417 priced models.
Alternatives
More from Stepfun
Stepfun
$0.438
/M blended
Alternatives
Similar price, other providers
$0.150
/M blended
$0.150
/M blended
Qwen (Alibaba)
$0.150
/M blended
Mistral
$0.150
/M blended
Google
$0.152
/M blended
Qwen: Qwen3 235B A22B Instruct 2507
Qwen (Alibaba)
$0.153
/M blended
Within ±50% of $0.150/M blended.
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