[ StepFun ]

Step 3.7 Flash

Step 3.7 Flash from StepFun: a text model for chat and completions, with a 262,144-token context window and up to 256K output tokens. Routed to the cheapest provider. At or below list. Pay per token in USDF, with no subscription and no minimum. Streaming and the OpenAI-compatible request format are supported.

Get an API key Try in Playground

StepFunstep-3.7-flashAvailabletextContext window: 262,144 tokens

Input

$0.20

per 1M tokens

Output

$1.15

per 1M tokens

Cached input

$0.04

per 1M tokens

Context window

262,144

tokens

Model ID: step-3.7-flash
Modality: text
Unit: USD per 1M tokens
Endpoints: /v1/chat/completions
Max output: 256,000 tokens
Saving vs list: 4.76%

Data policy

Zero retentionNo training

Make your first request

Use any OpenAI-compatible SDK. Change the base URL, keep everything else. Responses include a receipt with the exact cost. No key yet? Create one.

No account: send the same request to /x402/v1/chat/completions without credentials and the gateway answers 402 with the quote. Pay per request.

POST /v1/chat/completions

curl https://api.usdf.fi/v1/chat/completions \
  -H "Authorization: Bearer $USDF_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "step-3.7-flash", "messages": [{"role": "user", "content": "Hello"}]}'