StepFun Step 3.5 Flash vs NotebookLM

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

NotebookLM

B
7.8/10

Google's free research assistant that turns your documents into an AI you can query -- and a podcast you can listen to

CategoryStepFun Step 3.5 FlashNotebookLM
Ease of Use6.08.0
Output Quality8.07.0
Value9.09.5
Features8.06.5
Overall7.87.8

Pricing Comparison

FeatureStepFun Step 3.5 FlashNotebookLM
Free TierYesYes
Starting Price$0$0

Which Should You Pick?

Pick StepFun Step 3.5 Flash if...

  • Higher output quality (8 vs 7)
  • More features (8 vs 6.5)

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 NotebookLM if...

  • Easier to use (8 vs 6)

Students researching papers, professionals who need to quickly digest long documents, and anyone who wants to turn a pile of PDFs into something they can query and listen to.

Visit NotebookLM

Our Verdict

StepFun Step 3.5 Flash and NotebookLM 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 NotebookLM works best for students researching papers, professionals who need to quickly digest long documents, and anyone who wants to turn a pile of pdfs into something they can query and listen to.