# Mellum2.1-12B-A2.5B-Thinking vs Phi-3.5-mini

> Side-by-side benchmark comparison for Mellum2.1-12B-A2.5B-Thinking and Phi-3.5-mini across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/mellum2-1-12b-a2-5b-thinking-vs-phi-3-5-mini
- Last updated: October 14, 2026

- Shared sourced benchmarks: 0
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

No benchmark verdict yet: there is no shared sourced benchmark row for Mellum2.1-12B-A2.5B-Thinking and Phi-3.5-mini.

## Summary

- Mellum2.1-12B-A2.5B-Thinking and Phi-3.5-mini do not currently share a sourced benchmark row. The mirror therefore compares metadata, pricing, context windows, and each model's separately reported coverage without naming a benchmark winner.

## Model Snapshot

| Property | Mellum2.1-12B-A2.5B-Thinking | Phi-3.5-mini |
|----------|----------|----------|
| Creator | JetBrains | Microsoft |
| Type | Open Weight | Open Weight |
| Reasoning | Reasoning | Non-Reasoning |
| Context | 128K | 128K |
| Independent public score (not head-to-head) | null | null |
| Benchmarks Covered | 7 | 8 |
| Pricing (input/output) | $0.00 / $0.00 | N/A |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Mellum2.1-12B-A2.5B-Thinking public-lane score: Coming soon
- Phi-3.5-mini public-lane score: Coming soon

| Benchmark | Mellum2.1-12B-A2.5B-Thinking | Phi-3.5-mini | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.1 | 17.4% | Coming soon | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Mellum2.1-12B-A2.5B-Thinking public-lane score: Coming soon
- Phi-3.5-mini public-lane score: Coming soon

| Benchmark | Mellum2.1-12B-A2.5B-Thinking | Phi-3.5-mini | Winner |
|-----------|-----------|-----------|--------|
| LiveCodeBench v6 | 82.0% | Coming soon | Coming soon |
| SWE-bench Verified | 47% | Coming soon | Coming soon |
| SWE-bench Pro | 28% | Coming soon | Coming soon |
| HumanEval | Coming soon | 62.8% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Mellum2.1-12B-A2.5B-Thinking public-lane score: Coming soon
- Phi-3.5-mini public-lane score: Coming soon

| Benchmark | Mellum2.1-12B-A2.5B-Thinking | Phi-3.5-mini | Winner |
|-----------|-----------|-----------|--------|
| BBH | Coming soon | 69% | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- Mellum2.1-12B-A2.5B-Thinking public-lane score: Coming soon
- Phi-3.5-mini public-lane score: Coming soon

| Benchmark | Mellum2.1-12B-A2.5B-Thinking | Phi-3.5-mini | Winner |
|-----------|-----------|-----------|--------|
| MMLU-Redux | 87.8% | Coming soon | Coming soon |
| GPQA-D | 64.6% | Coming soon | Coming soon |
| MMLU | Coming soon | 69% | Coming soon |
| MMLU-Pro | Coming soon | 47.4% | Coming soon |
| GPQA | Coming soon | 30.4% | Coming soon |
| MMMLU | Coming soon | 55.4% | Coming soon |

### Multilingual

- Winner: Insufficient shared evidence
- Mellum2.1-12B-A2.5B-Thinking public-lane score: Coming soon
- Phi-3.5-mini public-lane score: Coming soon

| Benchmark | Mellum2.1-12B-A2.5B-Thinking | Phi-3.5-mini | Winner |
|-----------|-----------|-----------|--------|
| MGSM | Coming soon | 47.9% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Mellum2.1-12B-A2.5B-Thinking public-lane score: Coming soon
- Phi-3.5-mini public-lane score: Coming soon

| Benchmark | Mellum2.1-12B-A2.5B-Thinking | Phi-3.5-mini | Winner |
|-----------|-----------|-----------|--------|
| IFEval | 90.6% | Coming soon | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- Mellum2.1-12B-A2.5B-Thinking public-lane score: Coming soon
- Phi-3.5-mini public-lane score: Coming soon

| Benchmark | Mellum2.1-12B-A2.5B-Thinking | Phi-3.5-mini | Winner |
|-----------|-----------|-----------|--------|
| GSM8K | Coming soon | 86.2% | Coming soon |

## FAQ

### Can I compare Mellum2.1-12B-A2.5B-Thinking and Phi-3.5-mini on BenchLM yet?

Not fully yet. BenchLM is tracking both models, but sourced benchmark coverage is still incomplete for a fair score-level comparison.

### Why does this page show "coming soon" values?

BenchLM only calls winners when public benchmark coverage is available on both sides of the comparison.

## Related Comparisons

- [Mellum2.1-12B-A2.5B-Thinking vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-mellum2-1-12b-a2-5b-thinking)
- [Phi-3.5-mini vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-phi-3-5-mini)
- [Mellum2.1-12B-A2.5B-Thinking vs GPT-6.1 Sol](/compare/gpt-6-1-sol-vs-mellum2-1-12b-a2-5b-thinking)
- [Phi-3.5-mini vs GPT-6.1 Sol](/compare/gpt-6-1-sol-vs-phi-3-5-mini)

## Explore More

- [Mellum2.1-12B-A2.5B-Thinking profile](/models/mellum2-1-12b-a2-5b-thinking)
- [Phi-3.5-mini profile](/models/phi-3-5-mini)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)
