Claude Opus 5.5 vs GPT-6 Luna

Price, context window & benchmark comparison

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Claude Opus 5.5

Anthropic
$4.00 / $20.00
Input / Output · per 1M tokens
VS
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GPT-6 Luna

OpenAI
$0.10 / $0.50
Input / Output · per 1M tokens
Compare different models
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Verdict: GPT-6 Luna is 40.0× cheaper than Claude Opus 5.5 on a typical 3:1 input/output mix. Claude Opus 5.5 scores higher on the Artificial Analysis Intelligence Index (57.6 vs 37.3). GPT-6 Luna has the larger context window (1.1M vs 1M).
Claude Opus 5.5GPT-6 Luna
Input price / 1M$4.00$0.10
Output price / 1M$20.00$0.50
Blended price (3:1)$8.00$0.20
Cached input / 1M$0.20$0.01
Context window1M1.1M
Max output128K128K
Intelligence index57.637.3
Coding index
Providers117
Best provider uptime (30m)100.0%100.0%
Vision inputYesYes
ReasoningYesYes
Tool callingYesYes
Released2026-09-222026-09-22
Retirement

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FAQ

Which is cheaper, Claude Opus 5.5 or GPT-6 Luna?

GPT-6 Luna is 40.0× cheaper than Claude Opus 5.5 on a typical 3:1 input/output mix.

Claude Opus 5.5 vs GPT-6 Luna: which has a bigger context window?

Claude Opus 5.5: 1,000,000 tokens. GPT-6 Luna: 1,050,000 tokens.

How much would 1 million requests cost?

At 2,000 input + 500 output tokens per request: Claude Opus 5.5 ≈ $18,000, GPT-6 Luna ≈ $450.00.

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