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Claude Opus 4.5 vs Nemotron 3 Ultra (550B A55B)

Claude Opus 4.5 and Nemotron 3 Ultra (550B A55B) are closely matched at 38.2 and 36.3 on the LLM Stats Score. Nemotron 3 Ultra (550B A55B) is 10.8x cheaper per token.

Anthropic · NVIDIA · Updated for 2026

Which is better?

Claude Opus 4.5 and Nemotron 3 Ultra (550B A55B) are closely matched on the overall LLM Stats Score at 38.2 and 36.3.

The models split the 2 individual benchmarks reported for both models evenly.

On price, Nemotron 3 Ultra (550B A55B) is roughly 10.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Nemotron 3 Ultra (550B A55B) also accepts a larger context window (262,144 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Opus 4.5

  • your work emphasizes reasoning — it leads those capability indexes

Choose Nemotron 3 Ultra (550B A55B)

  • cost matters — it's about 10.8x cheaper per token
  • you process long inputs — it offers a 262,144 token context window
  • you want the most recent training data — it shipped Jun 2026
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Opus 4.5
Anthropic
Nemotron 3 Ultra (550B A55B)
NVIDIA
Core performance indexes
LLM Stats Score
38.2
#66
36.3
#79
Reasoning
40.0
#55
35.4
#82
Coding
28.3
#57
21.0
#93
Agents
17.7
#73
12.5
#101
Cost, coverage & limits
Benchmark wins
1 of 2
1 of 2
Input price
$5.00 / M
$0.50 / M
Output price
$25.00 / M
$2.20 / M
Context window
200,000
262,144

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Claude Opus 4.5
Nemotron 3 Ultra (550B A55B)
Math
32.3#61
36.4#39
Tool use
21.1#54
2.8#166
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

11 reported for Claude Opus 4.5 · 26 for Nemotron 3 Ultra (550B A55B)

2 shared

Claude Opus 4.5 outperforms in 1 benchmarks (SWE-Bench Verified), while Nemotron 3 Ultra (550B A55B) is better at 0 benchmarks.

Claude Opus 4.5 has a slight edge in benchmark performance.

Sun Sep 20 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Nemotron 3 Ultra (550B A55B) costs less

For input processing, Claude Opus 4.5 ($5.00/1M tokens) is 10.0x more expensive than Nemotron 3 Ultra (550B A55B) ($0.50/1M tokens).

For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 11.4x more expensive than Nemotron 3 Ultra (550B A55B) ($2.20/1M tokens).

In conclusion, Claude Opus 4.5 is more expensive than Nemotron 3 Ultra (550B A55B).*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Sun Sep 20 2026 • llm-stats.com
Anthropic
Claude Opus 4.5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
NVIDIA
Nemotron 3 Ultra (550B A55B)
Input tokens$0.50
Output tokens$2.20
Best providerDeepinfra
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Nemotron 3 Ultra (550B A55B) accepts 262,144 input tokens compared to Claude Opus 4.5's 200,000 tokens. Nemotron 3 Ultra (550B A55B) can generate longer responses up to 262,144 tokens, while Claude Opus 4.5 is limited to 64,000 tokens.

Anthropic
Claude Opus 4.5
Input200,000 tokens
Output64,000 tokens
NVIDIA
Nemotron 3 Ultra (550B A55B)
Input262,144 tokens
Output262,144 tokens
Sun Sep 20 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Opus 4.5 supports multimodal inputs, whereas Nemotron 3 Ultra (550B A55B) does not.

Claude Opus 4.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Opus 4.5

Text
Images
Audio
Video

Nemotron 3 Ultra (550B A55B)

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Opus 4.5 is licensed under a proprietary license, while Nemotron 3 Ultra (550B A55B) uses OpenMDW License v1.1.

License differences may affect how you can use these models in commercial or open-source projects.

Claude Opus 4.5

Proprietary

Closed source

Nemotron 3 Ultra (550B A55B)

OpenMDW License v1.1

Open weights

Release Timeline

When each model was launched

Claude Opus 4.5 was released on 2025-11-24, while Nemotron 3 Ultra (550B A55B) was released on 2026-06-04.

Nemotron 3 Ultra (550B A55B) is 6 months newer than Claude Opus 4.5.

Claude Opus 4.5

Nov 24, 2025

9 months ago

Nemotron 3 Ultra (550B A55B)

Jun 4, 2026

3 months ago

6mo newer

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a knowledge cutoff of 2025-03-31, while Nemotron 3 Ultra (550B A55B) has a cutoff of 2025-09-30.

Nemotron 3 Ultra (550B A55B) has more recent training data (up to 2025-09-30), making it potentially better informed about events through that date compared to Claude Opus 4.5 (2025-03-31).

Claude Opus 4.5

Mar 2025

Nemotron 3 Ultra (550B A55B)

Sep 2025

6 mo newer

Provider Availability

Claude Opus 4.5 is available from Anthropic. Nemotron 3 Ultra (550B A55B) is available from DeepInfra.

Claude Opus 4.5

anthropic logo
Anthropic
Input Price:Input: $5.00/1MOutput Price:Output: $25.00/1M

Nemotron 3 Ultra (550B A55B)

deepinfra logo
Deepinfra
Input Price:Input: $0.50/1MOutput Price:Output: $2.20/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Claude Opus 4.5 and Nemotron 3 Ultra (550B A55B) side-by-side, then vote on the output you prefer.

Claude Opus 4.5
✓ Preferred
Nemotron 3 Ultra (550B A55B)
Open in Playground

FAQ

Common questions about Claude Opus 4.5 vs Nemotron 3 Ultra (550B A55B).

Which is better, Claude Opus 4.5 or Nemotron 3 Ultra (550B A55B)?

Claude Opus 4.5 and Nemotron 3 Ultra (550B A55B) are closely matched on the LLM Stats Score at 38.2 and 36.3. Claude Opus 4.5 is made by Anthropic and Nemotron 3 Ultra (550B A55B) is made by NVIDIA. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Opus 4.5 compare to Nemotron 3 Ultra (550B A55B) in benchmarks?

Claude Opus 4.5 scores Tau2 Telecom: 98.2%, MMMLU: 90.8%, Tau2 Retail: 88.9%, GPQA: 87.0%, SWE-Bench Verified: 80.9%. Nemotron 3 Ultra (550B A55B) scores RULER: 94.7%, IMO-AnswerBench: 92.3%, PinchBench: 90.0%, LiveCodeBench v6: 89.0%, GPQA: 87.0%.

Is Claude Opus 4.5 cheaper than Nemotron 3 Ultra (550B A55B)?

Nemotron 3 Ultra (550B A55B) is 10.0x cheaper for input tokens. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic. Nemotron 3 Ultra (550B A55B) costs $0.50/M input and $2.20/M output via deepinfra.

What are the context window sizes for Claude Opus 4.5 and Nemotron 3 Ultra (550B A55B)?

Claude Opus 4.5 supports 200K tokens and Nemotron 3 Ultra (550B A55B) supports 262K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Opus 4.5 and Nemotron 3 Ultra (550B A55B)?

Key differences include LLM Stats Score (38.2 vs 36.3), context window (200K vs 262K), input pricing ($5.00 vs $0.50/M), multimodal support (yes vs no), licensing (Proprietary vs OpenMDW License v1.1). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4.5 and Nemotron 3 Ultra (550B A55B)?

Claude Opus 4.5 is developed by Anthropic and Nemotron 3 Ultra (550B A55B) is developed by NVIDIA.

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