Step 3.5 Flash pricing and routing profile
Step 3.5 Flash from Stepfun lists at $0.10 per million input tokens and $0.30 per million output tokens, with a 262,144-token context window. Prices from OpenRouter's catalogue on 2026-09-28.
Tool callingReasoning control
Cost per 1,000 requests
| Request shape | List cost |
|---|---|
| Classification or routing (600 tokens in, 10 out) | $0.063 |
| Chat reply (2,000 in, 400 out) | $0.32 |
| Retrieval-augmented answer (8,000 in, 500 out) | $0.95 |
Before prompt caching. Try your own shape in the cost calculator.
Can Gimbix route to it first?
Not as a first-answer model through OpenRouter: no host returns token log probabilities for Step 3.5 Flash. It can still be the model Gimbix falls back to when a cheaper model is unsure.
Cheaper models that can answer first
Models priced below Step 3.5 Flash that expose a confidence signal. Whether they answer your traffic as well is what a Gimbix pilot measures.
| Model | Input / output per 1M | Cheaper on a chat reply |
|---|---|---|
| Mistral Small 3.2 24B | $0.0938 / $0.25 | 10% |
| Qwen3 Coder 30B A3B Instruct | $0.07 / $0.28 | 21% |
| Nemotron 3.5 Lightning | $0.08 / $0.20 | 25% |
| Gemma 4 26B A4B | $0.0675 / $0.225 | 30% |
| Granite 4.2 8B | $0.06 / $0.25 | 31% |
| Nemotron 3 Nano 30B A3B | $0.05 / $0.20 | 44% |
Questions
How much does Step 3.5 Flash cost?
Step 3.5 Flash lists at $0.10 per million input tokens and $0.30 per million output tokens on OpenRouter as of 2026-09-28. A typical chat reply of 2,000 input and 400 output tokens costs about $0.32 per 1,000 requests.
What is the context window of Step 3.5 Flash?
262,144 tokens.
Can a cheaper model replace Step 3.5 Flash?
Sometimes. Gimbix proves it on your own traffic before routing: the cheaper model must match Step 3.5 Flash on one half of your requests and make at most three answers worse on the other.