Claude Opus 5.5 vs Nemotron 3 Ultra
Claude Opus 5.5 leads Nemotron 3 Ultra on coding, 88.8 to 30.0 on the Vibe Coding Index, and Nemotron 3 Ultra costs 8.3x less per output token ($2.40 vs $20.00 per million). Updated October 22, 2026; 52 benchmarks have a result for both.
vs boards won of 52 shared
Claude Opus 5.5 or Nemotron 3 Ultra: which to pick
Pick Claude Opus 5.5 for coding: it scores 88.8 on the Vibe Coding Index against 30.0 for Nemotron 3 Ultra.
Pick Nemotron 3 Ultra for output tokens 8.3x cheaper ($2.40 vs $20.00 per million).
Model AClaude Opus 5.5Anthropic88.8/1005 independent benchmarksNo cost per solved taskModel BNemotron 3 UltraNVIDIA30.0/1003 independent benchmarksNo cost per solved task
- Shared results
- 52
- Claude Opus 5.5 only
- 60
- Nemotron 3 Ultra only
- 19
- Like-for-like categories
- 8 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, six public coding benchmarks
Claude Opus 5.5
Claude Opus 5.5 scores 88.8 against 30.0.
5 and 3 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Opus 5.5
Claude Opus 5.5 leads, 57.6 against 22.9.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Nemotron 3 Ultra has a AA Agentic Index result, 20.1.
Directional only
Reasoning
GPQA Diamond
No call
Only Nemotron 3 Ultra has a GPQA Diamond result, 86.1%.
Directional only
Knowledge
MMLU Pro
No call
Only Nemotron 3 Ultra has a MMLU Pro result, 85.8%.
Directional only
Web design
Design Arena: websites
Claude Opus 5.5
Claude Opus 5.5 leads, 1335 against 1145.
Same board, both measured
General
Vals Index
No call
Only Claude Opus 5.5 has a Vals Index result, 70.2%.
Directional only
Long documents
Listed context window
Claude Opus 5.5
Claude Opus 5.5 takes 1M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Nemotron 3 Ultra
Claude Opus 5.5 $0.014, Nemotron 3 Ultra $0.0018 per turn.
List prices
At a glance
- Coding index
- Claude Opus 5.5 88.8 from 5 benchmarks, Nemotron 3 Ultra 30.0 from 3 benchmarks.
- Widest category
- Coding, 39.2 points apart on average over 8 shared benchmarks.
- Widest single gap
- ProofBench: Claude Opus 5.5 100.0% against Nemotron 3 Ultra 2.0%, 98.0 points apart on a 0 to 100 scale.
- Output price
- Claude Opus 5.5 $20.00 against Nemotron 3 Ultra $2.40 per million output tokens, 8.3x apart.
- Context window
- Claude Opus 5.5 takes 1M tokens, Nemotron 3 Ultra 262K.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | Claude Opus 5.5 | Bars | Nemotron 3 Ultra | Ties |
|---|---|---|---|---|
| Coding | 8 | 0 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 4 | 0 | ||
| Reasoning | 6 | 0 | ||
| Math | 4 | 0 | ||
| Knowledge | 5 | 0 | ||
| Web design | 7 | 0 | ||
| General | 16 | 0 | ||
| All shared boards | 52 | 0 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index80
| Benchmark | Claude Opus 5.5 | Nemotron 3 Ultra | Leader |
|---|---|---|---|
| LiveBench coding | 96.3% | Not measured | Only Claude Opus 5.5 measured |
| LMArena WebDev | 1807 | Not measured | Only Claude Opus 5.5 measured |
| AA Coding Index | Not measured | 49.3 | Only Nemotron 3 Ultra measured |
| LiveCodeBench (Vals AI) | Not measured | 86.0% | Only Nemotron 3 Ultra measured |
| SWE-bench Verified (Vals AI) | Not measured | 69.0% | Only Nemotron 3 Ultra measured |
| Terminal-Bench 4 (Vals AI) | 65.2% | Not measured | Only Claude Opus 5.5 measured |
| Vibe Code Bench (Vals AI) | 90.3% | 7.6% | Claude Opus 5.5 |
| Code migration (Vals AI) | 66.7% | 4.9% | Claude Opus 5.5 |
| ProgramBench (Vals AI) | 18.5% | 0.0% | Claude Opus 5.5 |
| IOI (Vals AI) | 95.1% | Not measured | Only Claude Opus 5.5 measured |
| Terminal-Bench 2.1 (Vals AI) | 87.6% | 50.9% | Claude Opus 5.5 |
| SWE-bench Multimodal (Vals AI) | 70.2% | Not measured | Only Claude Opus 5.5 measured |
| Vibe Code Bench 1-100 (Vals AI) | 30.4% | Not measured | Only Claude Opus 5.5 measured |
| CyberBench (Vals AI) | 74.6% | Not measured | Only Claude Opus 5.5 measured |
| SciCode | 66.9% | 40.3% | Claude Opus 5.5 |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 36.4% | Only Nemotron 3 Ultra measured |
| FrontierCode | 54.6% | 13.6% | Claude Opus 5.5 |
| FrontierSWE | 62.3% | Not measured | Only Claude Opus 5.5 measured |
| WeirdML | Not measured | 43.5% | Only Nemotron 3 Ultra measured |
| MirrorCode | 77.4% | Not measured | Only Claude Opus 5.5 measured |
| ALE-Bench | 2147.4 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: coding | 1545 | 1468 | Claude Opus 5.5 |
| LMArena Text: software and IT | 1538 | 1468 | Claude Opus 5.5 |
| LMArena WebDev: React | 1855 | Not measured | Only Claude Opus 5.5 measured |
| LMArena WebDev: HTML | 1753 | Not measured | Only Claude Opus 5.5 measured |
| LMArena WebDev: from an image | 1753 | Not measured | Only Claude Opus 5.5 measured |
| SciCode | 18.5% | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 16 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Opus 5.5 | Nemotron 3 Ultra | Leader |
|---|---|---|---|
| AA Intelligence Index | 57.6 | 22.9 | Claude Opus 5.5 |
| Epoch Capabilities Index | 168.8 | 146.0 | Claude Opus 5.5 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Opus 5.5 | Nemotron 3 Ultra | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 20.1 | Only Nemotron 3 Ultra measured |
| Design Arena: agents building web apps | 1316 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: agents building mobile apps | 1310 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: spreadsheets | 1385 | Not measured | Only Claude Opus 5.5 measured |
| LiveBench research | 85.0% | Not measured | Only Claude Opus 5.5 measured |
| LiveBench browser | 80.0% | Not measured | Only Claude Opus 5.5 measured |
| LiveBench long agentic | 85.0% | Not measured | Only Claude Opus 5.5 measured |
| SREBench (Vals AI) | 33.6% | Not measured | Only Claude Opus 5.5 measured |
| Finance Agent (Vals AI) | 58.6% | 37.7% | Claude Opus 5.5 |
| Tax Agent Bench (Vals AI) | 45.6% | Not measured | Only Claude Opus 5.5 measured |
| Legal Research Bench (Vals AI) | 50.5% | 15.4% | Claude Opus 5.5 |
| Harvey's Legal Agent Benchmark (Vals AI) | 9.2% | Not measured | Only Claude Opus 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 75.9% | 31.7% | Claude Opus 5.5 |
| BioMysteryBench (Vals AI) | 79.3% | Not measured | Only Claude Opus 5.5 measured |
| Terminal-Bench-Science (Vals AI) | 47.1% | Not measured | Only Claude Opus 5.5 measured |
| Vals Science Index | 58.7% | Not measured | Only Claude Opus 5.5 measured |
| Time Horizon Index (Vals AI) | 91.3% | Not measured | Only Claude Opus 5.5 measured |
| CUA-bench (Vals AI) | 14.0% | Not measured | Only Claude Opus 5.5 measured |
| Robo-bench (Vals AI) | 14.6% | Not measured | Only Claude Opus 5.5 measured |
| τ²-Bench Telecom | Not measured | 83.3% | Only Nemotron 3 Ultra measured |
| APEX-Agents | 73.5% | 22.7% | Claude Opus 5.5 |
| Remote Labor Index | 21.3% | Not measured | Only Claude Opus 5.5 measured |
| SpireClimb | 3.3% | Not measured | Only Claude Opus 5.5 measured |
| Vending-Bench 2 | $9,235 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Search | 1213 | Not measured | Only Claude Opus 5.5 measured |
| MCP Atlas | Not measured | 63.1% | Only Nemotron 3 Ultra measured |
| Neither model has a result on the other 16 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Opus 5.5 | Nemotron 3 Ultra | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 86.1% | Only Nemotron 3 Ultra measured |
| LiveBench reasoning | 92.2% | Not measured | Only Claude Opus 5.5 measured |
| MysteryMechanism (Vals AI) | 49.5% | Not measured | Only Claude Opus 5.5 measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 86.7% | Only Nemotron 3 Ultra measured |
| Humanity's Last Exam (Artificial Analysis run) | 61.4% | 28.4% | Claude Opus 5.5 |
| GPQA Diamond (Epoch AI run) | 90.6% | 85.4% | Claude Opus 5.5 |
| ARC-AGI | 98.5% | Not measured | Only Claude Opus 5.5 measured |
| ARC-AGI-2 | 93.3% | Not measured | Only Claude Opus 5.5 measured |
| Chess puzzles | 67.0% | Not measured | Only Claude Opus 5.5 measured |
| Mystery game puzzles | 71.0% | 20.0% | Claude Opus 5.5 |
| EBR-bench | 71.4% | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: hard prompts | 1536 | 1452 | Claude Opus 5.5 |
| LMArena Text: expert | 1549 | 1472 | Claude Opus 5.5 |
| LMArena Text: hard prompts in English | 1535 | 1453 | Claude Opus 5.5 |
| LMArena Vision: diagrams | 1345 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Vision: homework | 1362 | Not measured | Only Claude Opus 5.5 measured |
| Humanity's Last Exam (Scale run) | 55.0% | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 6 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Opus 5.5 | Nemotron 3 Ultra | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | 86.7% | Claude Opus 5.5 |
| FrontierMath, tiers 1 to 3 | 91.2% | Not measured | Only Claude Opus 5.5 measured |
| FrontierMath, tier 4 | 95.0% | Not measured | Only Claude Opus 5.5 measured |
| ProofBench | 100.0% | 2.0% | Claude Opus 5.5 |
| LMArena Text: math | 1518 | 1457 | Claude Opus 5.5 |
| LMArena Text: mathematical work | 1516 | 1461 | Claude Opus 5.5 |
| MathArena | 79.0% | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Claude Opus 5.5 | Nemotron 3 Ultra | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 85.8% | Only Nemotron 3 Ultra measured |
| LegalBench (Vals AI) | Not measured | 82.1% | Only Nemotron 3 Ultra measured |
| CorpFin (Vals AI) | Not measured | 65.5% | Only Nemotron 3 Ultra measured |
| TaxEval (Vals AI) | Not measured | 73.1% | Only Nemotron 3 Ultra measured |
| MedCode (Vals AI) | 49.8% | 38.6% | Claude Opus 5.5 |
| SimpleQA Verified | 72.2% | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: science | 1524 | 1465 | Claude Opus 5.5 |
| LMArena Text: medicine and healthcare | 1509 | 1456 | Claude Opus 5.5 |
| LMArena Text: legal and government | 1518 | 1452 | Claude Opus 5.5 |
| LMArena Text: business and finance | 1494 | 1434 | Claude Opus 5.5 |
| FACTS Benchmark Suite | 65.3% | Not measured | Only Claude Opus 5.5 measured |
| PRBench Legal | 47.6% | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 8 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index70
| Benchmark | Claude Opus 5.5 | Nemotron 3 Ultra | Leader |
|---|---|---|---|
| Design Arena: websites | 1335 | 1145 | Claude Opus 5.5 |
| Design Arena: UI components | 1382 | 1135 | Claude Opus 5.5 |
| Design Arena: game dev | 1455 | 1138 | Claude Opus 5.5 |
| Design Arena: data viz | 1398 | 1141 | Claude Opus 5.5 |
| Design Arena: 3D | 1476 | 1131 | Claude Opus 5.5 |
| Design Arena: all code categories | 1388 | 1146 | Claude Opus 5.5 |
| Design Arena: SVG | 1328 | 1069 | Claude Opus 5.5 |
| Design Arena: ASCII art | Not measured | 1100 | Only Nemotron 3 Ultra measured |
| LiveBench design | 86.9% | Not measured | Only Claude Opus 5.5 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index160
| Benchmark | Claude Opus 5.5 | Nemotron 3 Ultra | Leader |
|---|---|---|---|
| Vals Index | 70.2% | Not measured | Only Claude Opus 5.5 measured |
| LiveBench data analysis | 80.3% | Not measured | Only Claude Opus 5.5 measured |
| Public Benefits Bench (Vals AI) | 70.6% | Not measured | Only Claude Opus 5.5 measured |
| SAGE (Vals AI) | 45.8% | Not measured | Only Claude Opus 5.5 measured |
| MedScribe (Vals AI) | 91.4% | Not measured | Only Claude Opus 5.5 measured |
| IFBench | Not measured | 81.4% | Only Nemotron 3 Ultra measured |
| Long context reasoning (AA-LCR) | 84.7% | 79.3% | Claude Opus 5.5 |
| DTBench | 98.9% | 90.1% | Claude Opus 5.5 |
| LMCA | 68.2% | 36.9% | Claude Opus 5.5 |
| Furniture assembly | 83.3% | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text | 1516 | 1445 | Claude Opus 5.5 |
| LMArena Text: instruction following | 1537 | 1418 | Claude Opus 5.5 |
| LMArena Text: creative writing | 1535 | 1399 | Claude Opus 5.5 |
| LMArena Vision | 1321 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: English | 1519 | 1455 | Claude Opus 5.5 |
| LMArena Text: non-English | 1507 | 1427 | Claude Opus 5.5 |
| LMArena Text: Chinese | 1582 | 1497 | Claude Opus 5.5 |
| LMArena Text: German | Not measured | 1472 | Only Nemotron 3 Ultra measured |
| LMArena Text: Japanese | 1534 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: Korean | Not measured | 1384 | Only Nemotron 3 Ultra measured |
| LMArena Text: French | 1493 | 1472 | Claude Opus 5.5 |
| LMArena Text: Spanish | 1508 | 1455 | Claude Opus 5.5 |
| LMArena Text: Russian | 1517 | 1417 | Claude Opus 5.5 |
| LMArena Text: Polish | Not measured | 1385 | Only Nemotron 3 Ultra measured |
| LMArena Text: multi-turn | 1501 | 1411 | Claude Opus 5.5 |
| LMArena Text: longer queries | 1532 | 1437 | Claude Opus 5.5 |
| LMArena Text: writing and language | 1532 | 1406 | Claude Opus 5.5 |
| LMArena Text: entertainment and media | 1515 | 1397 | Claude Opus 5.5 |
| LMArena Vision: English | 1317 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Vision: reading text | 1326 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Vision: creative writing | 1320 | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 17 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Opus 5.5 | Nemotron 3 Ultra | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
Claude Opus 5.5$0.014Fits in one request
Nemotron 3 Ultra$0.0018Fits in one request
Nemotron 3 Ultra costs less
Repository review
50K input + 3K output tokens
Claude Opus 5.5$0.260Fits in one request
Nemotron 3 Ultra$0.037Fits in one request
Nemotron 3 Ultra costs less
Agent loop
200K input + 10K output tokens
Claude Opus 5.5$1.00Fits in one request
Nemotron 3 Ultra$0.144Fits in one request
Nemotron 3 Ultra costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | Anthropic Claude Opus 5.5 | NVIDIA Nemotron 3 Ultra |
|---|---|---|
| Maker | Anthropic | NVIDIA |
| Weights | No public weights listed | Open weights |
| Released | September 22, 2026 | June 4, 2026 |
| Context window | 1M | 262K |
| Input $/Mtok | $4.00 | $0.60 |
| Output $/Mtok | $20.00 | $2.40 |
| Coding index | 88.8 | 30.0 |
| Independent measurements behind it | 5 | 3 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Opus 5.5 better than Nemotron 3 Ultra for coding?
Pick Claude Opus 5.5 for coding: it scores 88.8 on the Vibe Coding Index against 30.0 for Nemotron 3 Ultra. Pick Nemotron 3 Ultra for output tokens 8.3x cheaper ($2.40 vs $20.00 per million).
Which is cheaper, Claude Opus 5.5 or Nemotron 3 Ultra?
Claude Opus 5.5 costs $4.00 per million input tokens and $20.00 per million output tokens; Nemotron 3 Ultra costs $0.60 and $2.40. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Opus 5.5 or Nemotron 3 Ultra?
Claude Opus 5.5, with 1M tokens against 262K.
How many benchmarks is the Claude Opus 5.5 vs Nemotron 3 Ultra comparison based on?
52 benchmarks have a result for both models as of October 22, 2026. Claude Opus 5.5's coding index rests on 5 independent benchmarks and Nemotron 3 Ultra's on 3. Where only one model has a result, the page says so instead of naming a winner.