stepfun · Open weights
Step 3.7 Flash Thinking
Step 3.7 Flash Thinking is StepFun's high-efficiency multimodal MoE model with visible reasoning enabled for deeper agentic coding, long-context reasoning, tool use, and native image/video understanding. ⚠️ Note: This model routes through StepFun, so privacy and logging guarantees may be limited.
- Reasoning
- Tools
- Vision
- Structured output
- Video input
- Input
- Text, Images, Video
- Output
- Text
- Reasoning effort
- none · low · medium · high
- Discovery tier
- Open weights
Pricing
USD per 1M tokens- Input
- $0.20
- Output
- $1.15
- Cache read
- $0.04
Reference prices as published by the model provider. API example
Specifications
- Context window
- 262.1K
- Max output
- 256K
- Average output (7 days)
- 7.1K tokens
- Longer than 99% of 468 models
Side by side
Step 3.7 Flash Thinking compared
Specifications, prices, speed and benchmark scores next to each other. Benchmarks below show every compared model too.
| Step 3.7 Flash ThinkingstepfunThis model | GLM 5.3 Flash UncensoredZ.aiRemove | |
|---|---|---|
| Provider | stepfun | Z.ai |
| Discovery tier | Open weights | Open weights |
| Added | May 29, 2026 | Jul 29, 2026 |
| Limits | ||
| Context window | 262.14K | 1.05MBest |
| Max output | 256KBest | 32.77K |
| Average output | 7.1K tokens | 692 tokens |
| Pricing, USD per 1M tokens | ||
| Input | $0.20 | $0.20 |
| Output | $1.15 | $0.80Best |
| Cache read | $0.04Best | $0.07 |
| Performance | ||
| Throughput | — | 208.6 tok/s |
| Time to first token | — | 2.9 s |
| Request success (24h) | 100.0%Best | 99.8% |
| Capabilities | ||
| Reasoning | Yes | Yes |
| Tools | Yes | Yes |
| Vision | Yes | Yes |
| Structured output | Yes | Yes |
| Video input | Yes | No |
| Reasoning effort | none, low, medium, high | low, high |
Public evaluations
Benchmarks
Independent evaluation results, with how each score ranks among the models in the Noumen catalog.
- Step 3.7 Flash Thinking
- GLM 5.3 Flash Uncensored
| Leaderboard | Step 3.7 Flash Thinking | GLM 5.3 Flash Uncensored |
|---|---|---|
| Combined | Not in top 20 | #17 · 8.5% |
Ranks among Noumen catalog models on Combined leaderboards. Only top-20 placements are listed.
- Step 3.7 Flash Thinking
- GLM 5.3 Flash Uncensored
| Leaderboard | Step 3.7 Flash Thinking | GLM 5.3 Flash Uncensored |
|---|---|---|
| Usage Share | Not in top 20 | #3 · 7.3% |
Ranks among Noumen catalog models on Usage leaderboards. Only top-20 placements are listed.
Live routing data
Performance and reliability
Recent averages across requests routed for this model. Your own speed depends on prompt length, reasoning effort and load.
- Prompt cache hits
- 0.0%
- About $0.20 per 1M input tokens with caching
- Request success (24h)
- 100.0%
- Reliable
Cache hits are the share of input tokens recently served from a prompt cache across all requests. They are not a forecast of your own hit rate.
- Healthy (98% or more)
- Degraded (90–98%)
- Down (under 90%)
- No requests
Developers
Use it through the API
Noumen’s API is OpenAI-compatible: any Chat Completions client works with a base URL and a key.
curl https://www.noumen.xyz/api/v1/chat/completions \
-H "Authorization: Bearer $NOUMEN_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "stepfun/step-3.7-flash:thinking",
"reasoning_effort": "medium",
"messages": [{ "role": "user", "content": "Explain this stack trace." }]
}'import os
from openai import OpenAI
client = OpenAI(base_url="https://www.noumen.xyz/api/v1", api_key=os.environ["NOUMEN_API_KEY"])
reply = client.chat.completions.create(
model="stepfun/step-3.7-flash:thinking",
messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)stepfun
Related models
Other stepfun models, starting with the same family.