Step 3.5 Flash (free) pricing
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.... This page tracks 1 listing in total. Highlighted lows are $0.0000 per million input and $0.0000 per million output (see table for which seller matches each).
Pricing across providers
All figures are list prices per million tokens unless a column says otherwise. 1 offer is listed for Step 3.5 Flash (free). Best input in this view: Openrouter.
| Provider | Input / 1M | Output / 1M | Cached input | Batch |
|---|---|---|---|---|
O Openrouter | $0.0000 | $0.0000 | — | — |
Input vs output · 1M tokens
Cost calculator
Use this block to stress test Step 3.5 Flash (free) cost without a spreadsheet. All estimates come from public list rates in this page.
Model specifications
These fields describe Step 3.5 Flash (free) as we store it (source: Stepfun). They sit next to price so buyers can check limits and tools in one place.
- Context window
- 256,000 tokens
- Max output
- 256,000 tokens
- Vision (images)
- No
- Tool / function calling
- Yes
- Streaming
- Yes
- Released
- Jan 2026
- Primary provider
- Stepfun
- Model family
- N/A
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Frequently asked questions
Read these after the table if you want plain language around Step 3.5 Flash (free) rates. The short model note from our index: 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....
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Other models by Stepfun with live pricing in our catalog.