StepFun Step 3.5 Flash vs InVideo AI

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

InVideo AI

B
7.3/10

Turn text prompts into fully edited videos with stock footage, voiceover, and music

CategoryStepFun Step 3.5 FlashInVideo AI
Ease of Use6.09.0
Output Quality8.06.0
Value9.07.0
Features8.07.0
Overall7.87.3

Pricing Comparison

FeatureStepFun Step 3.5 FlashInVideo AI
Free TierYesYes
Starting Price$0$0

Which Should You Pick?

Pick StepFun Step 3.5 Flash if...

  • Higher output quality (8 vs 6)
  • 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 InVideo AI if...

  • Easier to use (9 vs 6)

Marketers and small business owners who need quick social media or explainer videos and don't have a video editing background.

Visit InVideo AI

Our Verdict

StepFun Step 3.5 Flash edges out InVideo AI with a 7.8 vs 7.3 overall score. Both are solid picks, but StepFun Step 3.5 Flash has the advantage in output quality.