# GPT-4.1 nano vs Mellum2-12B-A2.5B-Instruct

> Side-by-side benchmark comparison for GPT-4.1 nano and Mellum2-12B-A2.5B-Instruct across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-4-1-nano-vs-mellum2-12b-a2-5b-instruct
- Last updated: September 4, 2026

- Shared sourced benchmarks: 2
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Evidence is too thin for a benchmark verdict: GPT-4.1 nano and Mellum2-12B-A2.5B-Instruct share only 2 sourced benchmark rows.

## Summary

- Only 2 shared sourced benchmark rows are available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- GPT-4.1 nano has the larger published context window at 1M.

## Model Snapshot

| Property | GPT-4.1 nano | Mellum2-12B-A2.5B-Instruct |
|----------|----------|----------|
| Creator | OpenAI | JetBrains |
| Type | Proprietary | Open Weight |
| Reasoning | Non-Reasoning | Non-Reasoning |
| Context | 1M | 128K |
| Independent public score (not head-to-head) | 28.43 | null |
| Benchmarks Covered | 4 | 6 |
| Pricing (input/output) | $0.10 / $0.40 | N/A |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- GPT-4.1 nano public-lane score: 32 (Estimated · #137/151)
- Mellum2-12B-A2.5B-Instruct public-lane score: 47.8 (Estimated · #82/151)

| Benchmark | GPT-4.1 nano | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| BFCL v4 | Coming soon | 44.2% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- GPT-4.1 nano public-lane score: 32.3 (Estimated · #164/183)
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

| Benchmark | GPT-4.1 nano | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| LiveCodeBench v6 | Coming soon | 37.2% | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- GPT-4.1 nano public-lane score: 25.3 (Unranked · 1 rankable row)
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

### Reasoning

- Winner: Insufficient shared evidence
- GPT-4.1 nano public-lane score: 34.9 (Unranked · 2 rankable rows)
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

### Knowledge

- Winner: Insufficient shared evidence
- GPT-4.1 nano public-lane score: 30.2 (Supported · #175/181)
- Mellum2-12B-A2.5B-Instruct public-lane score: 48.1 (Estimated · #103/181)

| Benchmark | GPT-4.1 nano | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| MMLU | 80.1% | Coming soon | Coming soon |
| GPQA | 50.3% | 40.9% | GPT-4.1 nano |
| MMLU-Redux | Coming soon | 78.1% | Coming soon |
| GPQA-D | Coming soon | 40.9% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- GPT-4.1 nano public-lane score: 36 (#106/120)
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

| Benchmark | GPT-4.1 nano | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| IFEval | 83.2% | 75.8% | GPT-4.1 nano |

### Mathematics

- Winner: Insufficient shared evidence
- GPT-4.1 nano public-lane score: 25.6 (Unranked · 1 rankable row)
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

| Benchmark | GPT-4.1 nano | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | 1.034% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between GPT-4.1 nano and Mellum2-12B-A2.5B-Instruct?

Not yet. The models share only 2 sourced benchmark rows, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [GPT-4.1 nano vs GPT-4.1](/compare/gpt-4-1-vs-gpt-4-1-nano)
- [Mellum2-12B-A2.5B-Instruct vs GPT-4.1](/compare/gpt-4-1-vs-mellum2-12b-a2-5b-instruct)
- [GPT-4.1 nano vs GPT-4.1 mini](/compare/gpt-4-1-mini-vs-gpt-4-1-nano)
- [Mellum2-12B-A2.5B-Instruct vs GPT-4.1 mini](/compare/gpt-4-1-mini-vs-mellum2-12b-a2-5b-instruct)

## Explore More

- [GPT-4.1 nano profile](/models/gpt-4-1-nano)
- [Mellum2-12B-A2.5B-Instruct profile](/models/mellum2-12b-a2-5b-instruct)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)