GPT-5.5 vs GPT-6 Luna
Price, context window & benchmark comparison
VS
Compare different models
Verdict: GPT-6 Luna is 56.3× cheaper than GPT-5.5 on a typical 3:1 input/output mix. GPT-5.5 scores higher on the Artificial Analysis Intelligence Index (38.4 vs 37.3).
| GPT-5.5 | GPT-6 Luna | |
|---|---|---|
| Input price / 1M | $5.00 | $0.10 |
| Output price / 1M | $30.00 | $0.50 |
| Blended price (3:1) | $11.25 | $0.20 |
| Cached input / 1M | $0.50 | $0.01 |
| Context window | 1.1M | 1.1M |
| Max output | 128K | 128K |
| Intelligence index | 38.4 | 37.3 |
| Coding index | 74.9 | — |
| Providers | — | 7 |
| Best provider uptime (30m) | — | 100.0% |
| Vision input | Yes | Yes |
| Reasoning | Yes | Yes |
| Tool calling | Yes | Yes |
| Released | 2026-04-24 | 2026-09-22 |
| Retirement | — | — |
Cost calculator
FAQ
Which is cheaper, GPT-5.5 or GPT-6 Luna?
GPT-6 Luna is 56.3× cheaper than GPT-5.5 on a typical 3:1 input/output mix.
GPT-5.5 vs GPT-6 Luna: which has a bigger context window?
GPT-5.5: 1,050,000 tokens. GPT-6 Luna: 1,050,000 tokens.
How much would 1 million requests cost?
At 2,000 input + 500 output tokens per request: GPT-5.5 ≈ $25,000, GPT-6 Luna ≈ $450.00.
More comparisons
GPT-5.5 vs GLM 5.3 PrimeGPT-5.5 vs Qwen3.8 Max PrimeGPT-5.5 vs Command A+GPT-5.5 vs GPT-6 Luna ProGPT-5.5 vs GPT-6 Sol ProGPT-5.5 vs GPT-6 SolGPT-5.5 vs Claude Opus 5.5GPT-5.5 vs MiMo-V2.6-Pro-UltraSpeedGPT-5.5 vs MiMo-V2.6-FlashGPT-5.5 vs Grok 4.7GPT-5.5 vs Qwen3.8 Omni FlashGPT-5.5 vs GLM 5.3 FlashXGPT-5.5 vs DeepSeek V4.1 FlashGPT-5.5 vs GPT-6 AstraGPT-5.5 vs GPT-6 Astra ProGPT-5.5 vs Qwen3.8 Max (0902)GPT-6 Luna vs GLM 5.3 PrimeGPT-6 Luna vs Qwen3.8 Max PrimeGPT-6 Luna vs Command A+GPT-6 Luna vs GPT-6 Luna ProGPT-6 Luna vs GPT-6 Sol ProGPT-6 Luna vs GPT-6 SolGPT-6 Luna vs Claude Opus 5.5GPT-6 Luna vs MiMo-V2.6-Pro-UltraSpeed