Claude Opus 4.5 vs GPT-5.6 Luna
Claude Opus 4.5 leads in 5 of 8 categories
Arena ELO
Claude Opus 4.5
Cheaper
Claude Opus 4.5
Faster
Claude Opus 4.5
Detailed Comparison
| Category | Claude Opus 4.5 | GPT-5.6 Luna |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Context Window | 200K WIN | 128K |
| Input Price ($/1M) | $5 WIN | $10 |
| Output Price ($/1M) | $25 WIN | $30 |
| Arena ELO | 1380 WIN | N/A |
| Coding | 80.9% SWE-bench | N/A |
| Reasoning | unknown | N/A |
| Speed (tokens/sec) | ~35 t/s WIN | N/A |
| Open Source | No | No |
Frequently Asked Questions
Which is cheaper, Claude Opus 4.5 or GPT-5.6 Luna?
Claude Opus 4.5 is approximately 25% cheaper than GPT-5.6 Luna per million tokens.
Which is better for coding, Claude Opus 4.5 or GPT-5.6 Luna?
Claude Opus 4.5 scores 80.9% SWE-bench on coding benchmarks, while GPT-5.6 Luna scores N/A.
Which has a larger context window?
Claude Opus 4.5 supports 200K context, while GPT-5.6 Luna supports 128K.
Is Claude Opus 4.5 or GPT-5.6 Luna open source?
Claude Opus 4.5 is proprietary. GPT-5.6 Luna is proprietary.
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