Compare / Qwen3.5 4B vs Phi-4-mini
Qwen3.5 4B vs Phi-4-mini
Updated November 2026
Verdict
Qwen3.5 4B scores higher on the Small LM Index: 59.9 vs 15.8. On the 7 benchmarks both labs report, Qwen3.5 4B wins 7 and Phi-4-mini wins 0. Both need about 4 GB of memory at 4-bit quantization. Neither model has a hosted API on OpenRouter, so you would run both yourself.
Pick Qwen3.5 4B if…
- you want the strongest model overall
- you mostly write code
- you need precise instruction following
- you build agents that call tools
- you work with long documents
- you need image input
- you want the more widely used model (more quantized builds and community support)
Pick Phi-4-mini if…
No clear advantage in the data we have.
Specifications
| Qwen3.5 4B | Phi-4-mini | |
|---|---|---|
| Small LM Index | 59.9 (likely 54–65) | 15.8 (likely 15–17) |
| Lab | Alibaba (Qwen) · China | Microsoft (Phi) · United States |
| Released | 2026-03-02 | 2025-02-26 |
| Parameters | 4B (dense) | 3.8B (dense) |
| Memory at 4-bit | ~3.3 GB | ~4 GB |
| Context window | 262K tokens | 128K tokens |
| Input | text, image, video | text |
| Reasoning | Hybrid (thinking on/off) | No thinking |
| License | Apache-2.0 | MIT |
| API price / 1M tokens | Self-host only | Self-host only |
| Hugging Face downloads (30 days) | 5.9M | 340.5K |
Benchmarks
Higher is better. Bold marks the winner where both labs report a score. ≈ marks the index model's estimate for a score that wasn't reported, ✓ an independent measurement and * a score measured by another lab.
| Benchmark | Qwen3.5 4B | Phi-4-mini |
|---|---|---|
| MMLU-Pro Knowledge | 79.1 | 46.5✓ |
| GPQA Diamond Knowledge | 77.1✓ | 33.1✓ |
| Humanity's Last Exam Reasoning | 9.9✓ | 4.4✓ |
| AIME Math | ≈ 82 | 3.0✓ |
| LiveCodeBench Coding | 55.8 | 12.6✓ |
| τ²-Bench Agentic | 92.1✓ | 8.2✓ |
| IFBench Instruction following | 52.0✓ | 21.1✓ |
| MMMU-Pro Vision | 65.4✓ | — |
| MATH-500 Math | — | 69.6✓ |
| AA-LCR Long context | 63.0✓ | 15.3✓ |
Scores are mostly reported by each lab with its own settings, so small gaps are noise. See the methodology. Open in the interactive comparison to add more models.
Questions
Which is better, Qwen3.5 4B or Phi-4-mini?
Qwen3.5 4B scores higher on the Small LM Index: 59.9 vs 15.8. On the 7 benchmarks both labs report, Qwen3.5 4B wins 7 and Phi-4-mini wins 0.
Which is cheaper to run?
Neither model has a hosted API on OpenRouter, so you would run both yourself. Both need about 4 GB of memory at 4-bit quantization.
Which has the longer context window?
Qwen3.5 4B has the longer context window: 262K tokens against 128K.
Can I use Qwen3.5 4B and Phi-4-mini commercially?
Qwen3.5 4B is released under Apache-2.0 and Phi-4-mini under MIT. Apache 2.0 and MIT allow commercial use; other licenses can add conditions, so read the license before shipping a product.