Claude Opus 5.5 vs Nemotron 3 Ultra 550B A55B
Wins 6 of 7 areas
Coding · Agents · Reasoning · Facts · Math · Long documents
Wins 1 of 7 areas
Following instructions
Claude Opus 5.5 is the stronger all-rounder.Nemotron 3 Ultra 550B A55B is cheaper and better at following instructions.
Scores updated · 28 tests both models report · How we compare
Where each one wins
Tests won in each of the seven areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- CodingWriting and fixing software50Claude Opus 5.55 of 5 tests
- ReasoningHard problems that need careful thinking40Claude Opus 5.54 of 4 tests
- AgentsCarrying out multi-step tasks on its own30Claude Opus 5.53 of 3 tests
- FactsGetting facts right instead of making them up21Claude Opus 5.52 of 3 tests
- MathCompetition and research-level math10Claude Opus 5.51 of 1 test
- Long documentsFinding answers in very long texts10Claude Opus 5.51 of 1 test
- Following instructionsDoing exactly what it is asked01Nemotron 3 Ultra 550B A55B1 of 1 test
Math, long documents and following instructions rest on a single test each.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
Nemotron 3 Ultra 550B A55B costs 86% less for the same work.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where Claude Opus 5.5 pulls ahead
- Complex command-line tasks across many fieldsTerminal-Bench 4.0+59.1points ahead
- Common-sense trick questionsSimpleBench+46.7points ahead
- Finds hard-to-locate facts by browsing the webBrowseComp+46.4points ahead
Where Nemotron 3 Ultra 550B A55B pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+28.9points ahead
- Follows detailed instructions exactlyLiveBench · Instruction Following+7.8points ahead
Every test, side by side
All 28 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Opus 5.5
- SWE-bench ProClaude Opus 5.5 by 40.289.949.7+40.2
- LiveBench · Agentic CodingClaude Opus 5.5 by 3371.738.7+33
- SciCodeClaude Opus 5.5 by 26.666.940.3+26.6
- SWE-bench MultilingualClaude Opus 5.5 by 26.293.967.7+26.2
- LiveBench · CodingClaude Opus 5.5 by 18.689.370.7+18.6
AgentsClaude Opus 5.5
- Terminal-Bench 4.0Claude Opus 5.5 by 59.159.60.5+59.1
- BrowseCompClaude Opus 5.5 by 46.490.844.4+46.4
- GDPValClaude Opus 5.5 by 42.668.325.7+42.6
ReasoningClaude Opus 5.5
- SimpleBenchClaude Opus 5.5 by 46.788.441.7+46.7
- Humanity's Last ExamClaude Opus 5.5 by 3361.428.4+33
- CritPtClaude Opus 5.5 by 28.631.73.1+28.6
- LiveBench · ReasoningClaude Opus 5.5 by 17.592.274.7+17.5
FactsClaude Opus 5.5
- AA-Omniscience · AccuracyClaude Opus 5.5 by 43.666.222.6+43.6
- SimpleQA VerifiedClaude Opus 5.5 by 39.872.232.4+39.8
- AA-Omniscience · Non-hallucinationNemotron 3 Ultra 550B A55B by 28.941.470.3+28.9
Following instructionsNemotron 3 Ultra 550B A55B
- LiveBench · Instruction FollowingNemotron 3 Ultra 550B A55B by 7.865.773.5+7.8
Other results10 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- HLE-DiamondClaude Opus 5.5 by 59.467.98.5+59.4
- Terminal-Bench-Science 0.1Claude Opus 5.5 by 59590+59
- CritPt v2 HardClaude Opus 5.5 by 536815+53
- AA-OmniscienceClaude Opus 5.5 by 46.846.4-0.4+46.8
- Toolathlon VerifiedClaude Opus 5.5 by 43.577.834.3+43.5
- AA IntelligenceClaude Opus 5.5 by 34.757.622.9+34.7
- HLE (with tools)Claude Opus 5.5 by 30.367.737.4+30.3
- livebench_data_analysisClaude Opus 5.5 by 25.880.354.5+25.8
- GDP (Surge AI)Claude Opus 5.5 by 21.226.25+21.2
- livebench_languageClaude Opus 5.5 by 15.586.370.8+15.5
Questions people ask
Which is better, Claude Opus 5.5 or Nemotron 3 Ultra 550B A55B?
Claude Opus 5.5 wins six of the seven areas where both have results: coding, agents, reasoning, facts, math and long documents. Nemotron 3 Ultra 550B A55B wins following instructions, and costs 86% less.
Which is better for coding?
Claude Opus 5.5. It wins 5 of the 5 coding tests both models report; Nemotron 3 Ultra 550B A55B wins none.
Which is cheaper?
Claude Opus 5.5 costs $4.00 per million input tokens and $20.00 per million output tokens; Nemotron 3 Ultra 550B A55B costs $0.60 and $2.70. That makes Nemotron 3 Ultra 550B A55B about 86% cheaper for the same work.
How do you compare the two?
We use the 28 benchmark tests both models have published scores on. The verdict counts the 18 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 10 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.