StepFun Step 3.5 Flash vs Microsoft Copilot

Which one should you pick? Here's the full breakdown.

Our Pick

StepFun Step 3.5 Flash

B
7.8/10

StepFun's (China) agent-focused open-weight model -- Step 3.5 Flash launched 2026-02-01. 196B sparse MoE, ~11B active. Benchmarks slightly ahead of DeepSeek V3.2 at over 3x smaller total size. Step 3 (321B / 38B active, Apache 2.0) and Step3-VL-10B multimodal also in the family

Microsoft Copilot

B
7.5/10

Microsoft's answer to ChatGPT -- free GPT-4 access with Bing search built in, but it feels like a corporate product

CategoryStepFun Step 3.5 FlashMicrosoft Copilot
Ease of Use6.08.0
Output Quality8.07.0
Value9.08.0
Features8.07.0
Overall7.87.5

Pricing Comparison

FeatureStepFun Step 3.5 FlashMicrosoft Copilot
Free TierYesYes
Starting Price$0$0

Which Should You Pick?

Pick StepFun Step 3.5 Flash if...

  • Higher output quality (8 vs 7)
  • Better value for money (9/10)
  • More features (8 vs 7)

Teams building agent systems on Chinese open-weight foundations who want something other than DeepSeek or Qwen, especially if agentic tool-use is the primary workload. Also good for Chinese-market products where StepFun's domestic tuning advantages matter. And for anyone looking to add diversity to their open-weight evaluation matrix beyond the top-3 Chinese labs.

Visit StepFun Step 3.5 Flash

Pick Microsoft Copilot if...

  • Easier to use (8 vs 6)

Users already deep in the Microsoft ecosystem who want free GPT-4 access with web search built in.

Visit Microsoft Copilot

Our Verdict

StepFun Step 3.5 Flash and Microsoft Copilot are extremely close overall. Your choice comes down to specific needs -- StepFun Step 3.5 Flash is better for teams building agent systems on chinese open-weight foundations who want something other than deepseek or qwen, especially if agentic tool-use is the primary workload, while Microsoft Copilot works best for users already deep in the microsoft ecosystem who want free gpt-4 access with web search built in.