StepFun: Step 3.5 Flash, Other — route, pricing & source

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....

OpenRoutermediumLast checked: Jun 2, 2026
Input
$0.0900 / 1M
/ 1M tokens
Output
$0.3000 / 1M
/ 1M tokens
Cached input
Not available
Not available
Cache write
Not available
Not available

Context and limits

Context window
262.1K
Max output
16,384
Input modalities
text
Output modalities
text
Weight access
Unknown
Availability
Unknown
Capability flags
ToolsJSONReasoningLong context

From source metadata + verification fields — confirm provider docs before production.

Benchmarks
No safely merged benchmark result for this model yet.

Access and license

Official API
No
Open weights
No
Self-hostable
No
License
Unknown

Source

Source
OpenRouter Models API
Confidence
medium
Route
OpenRouter
Last checked
Jun 2, 2026
Open source
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