MODELS / STEPFUN

Step 3.7 Flash

StepFun’s flagship multimodal reasoning model. Powered by a 198B-parameter / 11B-activation sparse MoE architecture, with native support for image and video understanding.

TEXTREASONINGIMPLICIT-CACHINGREASONINGTOOL-USEVISION
256K
CONTEXT WINDOW
256K
MAX OUTPUT TOKENS
$0.2 / 1M tokens
INPUT PRICE
$1.15 / 1M tokens
OUTPUT PRICE
QUICKSTART

Call it in one request.

OpenAI-compatible — change the base URL, and the setup is complete.

SHELL
curl https://enterprise.blackbox.ai/v1/chat/completions \
  -H "Authorization: Bearer $BLACKBOX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "blackboxai/stepfun/step-3.7-flash",
    "messages": [{ "role": "user", "content": "Hello!" }],
    "stream": true
  }'
INPUT: image, text, videoOUTPUT: textRELEASED: 2026-05-28
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