Model comparison
Mellum2-12B-A2.5B-Instruct vs Nemotron Ultra 253B
Head-to-head evidence from 0 shared benchmark results across 0 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Mellum2-12B-A2.5B-Instruct unranked (Not scored); Nemotron Ultra 253B #150 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Mellum2-12B-A2.5B-Instruct and Nemotron Ultra 253B share 0 comparable benchmark results. 0 of 8 categories are comparable. 5 results are unique to Mellum2-12B-A2.5B-Instruct; 11 to Nemotron Ultra 253B.
Updated July 23, 2026- Shared results
- 0
- Mellum2-12B-A2.5B-Instruct only
- 5
- Nemotron Ultra 253B only
- 11
- Comparable categories
- 0 / 8
Benchmark data for Mellum2-12B-A2.5B-Instruct and Nemotron Ultra 253B is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 0 shared benchmark results across 0 evidence categories; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
BenchLM has partial data for these models, but not enough overlapping benchmark coverage to produce a fair score-level comparison yet.
Mellum2-12B-A2.5B-Instruct has the larger context window at 128K, compared with 32K for Nemotron Ultra 253B.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Mellum2-12B-A2.5B-Instruct | Nemotron Ultra 253B | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Mellum2-12B-A2.5B-InstructNot available | Nemotron Ultra 253B$0 input / $0 output | A complete price comparison is not available. |
| Generation speedtokens per second | Mellum2-12B-A2.5B-InstructNot available | Nemotron Ultra 253BNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Mellum2-12B-A2.5B-InstructNot available | Nemotron Ultra 253BNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Mellum2-12B-A2.5B-Instruct128K | Nemotron Ultra 253B32K | Mellum2-12B-A2.5B-Instruct lists the larger context window. |
Benchmark Deep Dive
Agentic2 benchmarks
Coding1 benchmarks
| Benchmark | Mellum2-12B-A2.5B-Instruct | Nemotron Ultra 253B | Result |
|---|---|---|---|
| AA-SciCodeSource | — | 34.7% | Not comparable |
Reasoning2 benchmarks
Knowledge9 benchmarks
| Benchmark | Mellum2-12B-A2.5B-Instruct | Nemotron Ultra 253B | Result |
|---|---|---|---|
| MMLU-ReduxSource | 78.1% | — | Not comparable |
| GPQASource | 40.9% | — | Not comparable |
| GPQA-DSource | 40.9% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | — | 9.1% | Not comparable |
| AA-GPQA DiamondSource | — | 72.8% | Not comparable |
| AA-HLESource | — | 8.1% | Not comparable |
| AA-Omniscience IndexSource | — | -45.5% | Not comparable |
| AA-Omniscience AccuracySource | — | 19.9% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 81.7% | Not comparable |
Frequently Asked Questions (3)
Can I compare Mellum2-12B-A2.5B-Instruct and Nemotron Ultra 253B on BenchLM yet?
Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.
Why does this comparison show “coming soon”?
BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.
What data is available for Mellum2-12B-A2.5B-Instruct and Nemotron Ultra 253B today?
Nemotron Ultra 253B: $0.00 input / $0.00 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
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