MiniMax M2 / M2.5 vs StepFun Step 3.5 Flash
Which one should you pick? Here's the full breakdown.
MiniMax M2 / M2.5
MiniMax's open-weights frontier -- first open model to match Claude Opus 4.6 on SWE-Bench at 10-20× lower cost
StepFun Step 3.5 Flash
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
| Category | MiniMax M2 / M2.5 | StepFun Step 3.5 Flash |
|---|---|---|
| Ease of Use | 6.5 | 6.0 |
| Output Quality | 9.0 | 8.0 |
| Value | 9.5 | 9.0 |
| Features | 8.5 | 8.0 |
| Overall | 8.4 | 7.8 |
Pricing Comparison
| Feature | MiniMax M2 / M2.5 | StepFun Step 3.5 Flash |
|---|---|---|
| Free Tier | Yes | Yes |
| Starting Price | $0 | $0 |
Benchmark Head-to-Head
MiniMax M2.5 (230B/10B active MoE) benchmarks — StepFun Step 3.5 Flash has no published benchmarks
| Benchmark | Description | Score |
|---|---|---|
| MMLU-Pro | Harder multi-subject reasoning | 82.1% |
| GPQA Diamond | Graduate-level science questions | 76.8% |
| SWE-Bench Verified | 80.2% | |
| HumanEval | Python code generation | 91% |
| AIME 2025 | 85.3% |
Which Should You Pick?
Pick MiniMax M2 / M2.5 if...
- ✓Higher output quality (9 vs 8)
Agentic coding and tool-use workflows on a budget. Best price-to-SWE-Bench ratio of any open-weights model in 2026.
Visit MiniMax M2 / M2.5Pick StepFun Step 3.5 Flash if...
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 FlashOur Verdict
MiniMax M2 / M2.5 edges out StepFun Step 3.5 Flash with a 8.4 vs 7.8 overall score. Both are solid picks, but MiniMax M2 / M2.5 has the advantage in output quality.