GPT-5.6 Luna (High) vs GPT-6 Astra (Xhigh)
Which is better for the money: GPT-5.6 Luna (High) by OpenAI or GPT-6 Astra (Xhigh) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-27.
Trade-off
Verdict
Depends on your budget
GPT-6 Astra (Xhigh) scores 20.3 points higher (52.4 vs 32.1) but costs 35× as much to run the benchmark ($3803 vs $108; flagship vs mid-range cost classes). They are not alternatives at one budget: pick GPT-6 Astra (Xhigh) when you need intelligence above 32.1, and GPT-5.6 Luna (High) when 32.1 is enough.
| Metric | GPT-5.6 Luna (High) | GPT-6 Astra (Xhigh) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 32.1 | 52.4 | +63.2% GPT-6 Astra (Xhigh) is 63.2% more intelligent |
| Total AA cost (lower is better) | $108.15 | $3,802.98 | +3416.4% GPT-6 Astra (Xhigh) is 35× more expensive |
| End-to-end time (lower is better) | 16.31s | 181.54s | +1013.1% GPT-6 Astra (Xhigh) is 1013.1% slower |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $10.0 / $50.0 | |
| Input modalities | Text, Image | Text, Image |
GPT-6 Astra (Xhigh) vs GPT-5.6 Luna (High): 63.2% more intelligence, 3416.4% more cost to run the AA benchmark, and 1013.1% slower end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.6 Luna (High) is off the frontier: at the same or lower cost, Claude Haiku 5.5 (High) scores 37.80 for $94.1.
- GPT-6 Astra (Xhigh) is off the frontier: at the same or lower cost, Kimi K3.1 Pro scores 55.10 for $3117.
GPT-5.6 Luna (High)GPT-6 Astra (Xhigh)Today's Pareto frontierEvery other model
Matchup
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