Model comparison
Claude Opus 4.6 vs Nemotron Ultra 253B
Head-to-head evidence from 11 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Opus 4.6 #16 (Supported); Nemotron Ultra 253B #150 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Opus 4.6 and Nemotron Ultra 253B share 11 comparable benchmark results. 0 of 8 categories are comparable. 35 results are unique to Claude Opus 4.6; 0 to Nemotron Ultra 253B.
Updated July 20, 2026- Shared results
- 11
- Claude Opus 4.6 only
- 35
- Nemotron Ultra 253B only
- 0
- Comparable categories
- 0 / 8
Benchmark data for Claude Opus 4.6 and Nemotron Ultra 253B is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 11 shared benchmark results across 5 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.
Claude Opus 4.6 is priced at $5.00 input / $25.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Nemotron Ultra 253B. Claude Opus 4.6 has the larger context window at 1M, compared with 32K for Nemotron Ultra 253B.
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 | Claude Opus 4.6 | Δ | Nemotron Ultra 253B |
|---|---|---|---|
| Agentic | Claude Opus 4.673.0 | MarginNo overlap | Nemotron Ultra 253BNot measured |
| Coding | Claude Opus 4.668.1 | MarginNo overlap | Nemotron Ultra 253BNot measured |
| Knowledge | Claude Opus 4.669.1 | MarginNo overlap | Nemotron Ultra 253BNot measured |
| Math | Claude Opus 4.636.3 | MarginNo overlap | Nemotron Ultra 253BNot measured |
| Multimodal | Claude Opus 4.677.3 | MarginNo overlap | Nemotron Ultra 253BNot measured |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Opus 4.6 | Nemotron Ultra 253B | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Opus 4.6$5 input / $25 output | Nemotron Ultra 253B$0 input / $0 output | Nemotron Ultra 253B has the lower combined listed price. |
| Generation speedtokens per second | Claude Opus 4.640 tok/s | Nemotron Ultra 253BNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Opus 4.61.78 s | Nemotron Ultra 253BNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Opus 4.61M | Nemotron Ultra 253B32K | Claude Opus 4.6 lists the larger context window. |
Benchmark Deep Dive
Agentic10 benchmarks
| Benchmark | Claude Opus 4.6 | Nemotron Ultra 253B | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 65.4% | — | Not comparable |
| BrowseCompSource | 83.7% | — | Not comparable |
| OSWorld-VerifiedSource | 72.7% | — | Not comparable |
| τ²-bench resultsSource | 84.8% | 11.4% | Claude Opus 4.6 leads |
| Claw-EvalSource | 70.4% | — | Not comparable |
| DeepSearchQASource | 73.7% | — | Not comparable |
| CyberGymSource | 66.6% | — | Not comparable |
| Gert LabsSource | 61.85% | — | Not comparable |
| ResearchClawBenchSource | 19.9% | — | Not comparable |
| JobBenchSource | 36.7% | — | Not comparable |
Coding9 benchmarks
| Benchmark | Claude Opus 4.6 | Nemotron Ultra 253B | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 80.8% | — | Not comparable |
| SWE-bench Verified*Source | 75.6% | — | Not comparable |
| LiveCodeBench ProSource | 70.7% | — | Not comparable |
| SWE-bench ProSource | 53.4% | — | Not comparable |
| SWE-RebenchSource | 65.3% | — | Not comparable |
| React Native EvalsSource | 84.1% | — | Not comparable |
| Vibe Code BenchSource | 57.57% | — | Not comparable |
| AA-SciCodeSource | 45.7% | 34.7% | Claude Opus 4.6 leads |
| FrontierCode 1.1 MainSource | 26.9% | — | Not comparable |
Reasoning2 benchmarks
Knowledge15 benchmarks
| Benchmark | Claude Opus 4.6 | Nemotron Ultra 253B | Result |
|---|---|---|---|
| GPQASource | 91.3% | — | Not comparable |
| GPQA-DSource | 89.2% | — | Not comparable |
| SuperGPQASource | 95% | — | Not comparable |
| MMLU-ProSource | 82% | — | Not comparable |
| MMLU-Pro (Arcee)Source | 89.1% | — | Not comparable |
| HLESource | 53% | — | Not comparable |
| HLE w/o toolsSource | 40% | — | Not comparable |
| HealthBench HardSource | 14.8% | — | Not comparable |
| MedXpertQA (Text)Source | 52.1% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 37.8% | 9.1% | Claude Opus 4.6 leads |
| AA-GPQA DiamondSource | 84.0% | 72.8% | Claude Opus 4.6 leads |
| AA-HLESource | 18.6% | 8.1% | Claude Opus 4.6 leads |
| AA-Omniscience IndexSource | 3.5% | -45.5% | Claude Opus 4.6 leads |
| AA-Omniscience AccuracySource | 45.2% | 19.9% | Claude Opus 4.6 leads |
| AA-Omniscience Hallucination RateSource | 76.0% | 81.7% | Claude Opus 4.6 leads |
Math3 benchmarks
Multimodal6 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Opus 4.6 | Nemotron Ultra 253B | Result |
|---|---|---|---|
| AA-IFBenchSource | 44.6% | 38.2% | Claude Opus 4.6 leads |
Frequently Asked Questions (3)
Can I compare Claude Opus 4.6 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 Claude Opus 4.6 and Nemotron Ultra 253B today?
Claude Opus 4.6: $5.00 input / $25.00 output per 1M tokens 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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