Model comparison
Mellum2-12B-A2.5B-Instruct vs Nemotron 3 Ultra
Head-to-head evidence from 2 shared benchmark results across 1 category. Overall scores shown here use the public BenchAlign v5 ranking lane.
Evidence parity. Mellum2-12B-A2.5B-Instruct and Nemotron 3 Ultra share 2 comparable benchmark results. 2 of 8 categories are comparable. 3 results are unique to Mellum2-12B-A2.5B-Instruct; 36 to Nemotron 3 Ultra.
Updated July 23, 2026- Shared results
- 2
- Mellum2-12B-A2.5B-Instruct only
- 3
- Nemotron 3 Ultra only
- 36
- Comparable categories
- 2 / 8
Treat this as a split decision. Mellum2-12B-A2.5B-Instruct makes more sense if you would rather avoid the extra latency and token burn of a reasoning model; Nemotron 3 Ultra is the better fit if knowledge is the priority or you need the larger 1M context window.
Confidence note. This is a partial-evidence comparison with 2 shared benchmark results across 1 evidence category; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Mellum2-12B-A2.5B-Instruct and Nemotron 3 Ultra finish on the same BenchAlign overall score, so this is less about a single winner and more about where the edge shows up. The BenchAlign headline says tie; the benchmark table is where the real choice happens.
Nemotron 3 Ultra is the reasoning model in the pair, while Mellum2-12B-A2.5B-Instruct is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Nemotron 3 Ultra gives you the larger context window at 1M, compared with 128K for Mellum2-12B-A2.5B-Instruct.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | Mellum2-12B-A2.5B-Instruct | Δ | Nemotron 3 Ultra |
|---|---|---|---|
| Knowledge | Mellum2-12B-A2.5B-Instruct40.9 | Margin→ 12.9 | Nemotron 3 Ultra53.8 |
| Inst. Following | Mellum2-12B-A2.5B-Instruct75.8 | Margin→ 5.9 | Nemotron 3 Ultra81.7 |
| Agentic | Mellum2-12B-A2.5B-InstructNot measured | MarginNo overlap | Nemotron 3 Ultra51.3 |
| Coding | Mellum2-12B-A2.5B-InstructNot measured | MarginNo overlap | Nemotron 3 Ultra58.3 |
| Reasoning | Mellum2-12B-A2.5B-InstructNot measured | MarginNo overlap | Nemotron 3 Ultra61.9 |
| Multilingual | Mellum2-12B-A2.5B-InstructNot measured | MarginNo overlap | Nemotron 3 Ultra83.0 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
GPQA
KnowledgeA 40.9%B 87%Winner: Nemotron 3 UltraΔ 46.1GPQA: Mellum2-12B-A2.5B-Instruct scored 40.9%; Nemotron 3 Ultra scored 87%. Nemotron 3 Ultra wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Mellum2-12B-A2.5B-Instruct | Nemotron 3 Ultra | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Mellum2-12B-A2.5B-InstructNot available | Nemotron 3 Ultra$0 input / $0 output | A complete price comparison is not available. |
| Generation speedtokens per second | Mellum2-12B-A2.5B-InstructNot available | Nemotron 3 UltraNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Mellum2-12B-A2.5B-InstructNot available | Nemotron 3 UltraNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Mellum2-12B-A2.5B-Instruct128K | Nemotron 3 Ultra1M | Nemotron 3 Ultra lists the larger context window. |
Benchmark Deep Dive
Agentic14 benchmarks
| Benchmark | Mellum2-12B-A2.5B-Instruct | Nemotron 3 Ultra | Result |
|---|---|---|---|
| BFCL v4Source | 44.2% | — | Not comparable |
| Terminal-Bench 2.0Source | — | 56.4% | Not comparable |
| PinchBenchSource | — | 90.0% | Not comparable |
| BrowseCompSource | — | 44.4% | Not comparable |
| τ³-bench resultsSource | — | 70.9% | Not comparable |
| GDPval-AASource | — | 33.2% | Not comparable |
| HLE w/ toolsSource | — | 37.4% | Not comparable |
| AA Agentic IndexSource | — | 27.4% | Not comparable |
| τ²-bench resultsSource | — | 83.3% | Not comparable |
| GDPval-AASource | — | 1164 | Not comparable |
| AA BriefcaseSource | — | 870 | Not comparable |
| AA EnterpriseOps-GymSource | — | 28.9% | Not comparable |
| AA Harvey LABSource | — | 81.7% | Not comparable |
| terminalBenchHardSource | — | 36.4% | Not comparable |
Coding6 benchmarks
| Benchmark | Mellum2-12B-A2.5B-Instruct | Nemotron 3 Ultra | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | — | 71.9% | Not comparable |
| SWE MultilingualSource | — | 67.7% | Not comparable |
| SciCodeSource | — | 44.6% | Not comparable |
| Terminal-Bench 2.0Source | — | 56.4% | Not comparable |
| AA Coding IndexSource | — | 49.3% | Not comparable |
| AA-SciCodeSource | — | 39.9% | Not comparable |
Reasoning3 benchmarks
KnowledgeNemotron 3 Ultra wins13 benchmarks
| Benchmark | Mellum2-12B-A2.5B-Instruct | Nemotron 3 Ultra | Result |
|---|---|---|---|
| MMLU-ReduxSource | 78.1% | — | Not comparable |
| GPQASource | 40.9% | 87% | Nemotron 3 Ultra leads |
| GPQA-DSource | 40.9% | 87.0% | Nemotron 3 Ultra leads |
| HLESource | — | 26.7% | Not comparable |
| HLE w/o toolsSource | — | 26.7% | Not comparable |
| MMLU-ProSource | — | 86.8% | Not comparable |
| AA-Omniscience AccuracySource | — | 21.6% | Not comparable |
| Artificial Analysis Intelligence IndexSource | — | 37.8% | Not comparable |
| AA-GPQA DiamondSource | — | 86.7% | Not comparable |
| AA-HLESource | — | 26.6% | Not comparable |
| AA-Omniscience IndexSource | — | -0.8% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 28.5% | Not comparable |
| AA Openness IndexSource | — | 83.3% | Not comparable |
Multilingual1 benchmarks
| Benchmark | Mellum2-12B-A2.5B-Instruct | Nemotron 3 Ultra | Result |
|---|---|---|---|
| MMLU-ProXSource | — | 83% | Not comparable |
Multimodal1 benchmarks
| Benchmark | Mellum2-12B-A2.5B-Instruct | Nemotron 3 Ultra | Result |
|---|---|---|---|
| Design Arena WebsiteSource | — | 1129 | Not comparable |
Frequently Asked Questions (3)
Which is better, Mellum2-12B-A2.5B-Instruct or Nemotron 3 Ultra?
Mellum2-12B-A2.5B-Instruct and Nemotron 3 Ultra are tied on the BenchAlign overall score, so the right pick depends on which category matters most for your use case.
Which is better for knowledge tasks, Mellum2-12B-A2.5B-Instruct or Nemotron 3 Ultra?
Nemotron 3 Ultra has the edge for knowledge tasks in this comparison, averaging 53.8 versus 40.9. Inside this category, GPQA is the benchmark that creates the most daylight between them.
Which is better for instruction following, Mellum2-12B-A2.5B-Instruct or Nemotron 3 Ultra?
Nemotron 3 Ultra has the edge for instruction following in this comparison, averaging 81.7 versus 75.8. Mellum2-12B-A2.5B-Instruct stays close enough that the answer can still flip depending on your workload.
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