GPT-6 Luna (Medium) vs Grok 4.5 (High)
Which is better for the money: GPT-6 Luna (Medium) by OpenAI or Grok 4.5 (High) by SpaceXAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-24.
Trade-off
Verdict
Depends on your budget
Grok 4.5 (High) scores 8.9 points higher (38.8 vs 29.9) but costs 40× as much to run the benchmark ($1244 vs $31.2; premium vs budget cost classes). They are not alternatives at one budget: pick Grok 4.5 (High) when you need intelligence above 29.9, and GPT-6 Luna (Medium) when 29.9 is enough.
| Metric | GPT-6 Luna (Medium) | Grok 4.5 (High) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 29.9 | 38.8 | +29.8% Grok 4.5 (High) is 29.8% more intelligent |
| Total AA cost (lower is better) | $31.17 | $1,243.85 | +3890.5% Grok 4.5 (High) is 40× more expensive |
| End-to-end time (lower is better) | 8.25s | 18.82s | +128.1% Grok 4.5 (High) is 128.1% slower |
| Price per 1M tokens (in / out) | $0.10 / $0.50 | $2.00 / $6.00 | |
| Input modalities | Text, Image | Text, Image |
Grok 4.5 (High) vs GPT-6 Luna (Medium): 29.8% more intelligence, 3890.5% more cost to run the AA benchmark, and 128.1% slower end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-6 Luna (Medium) is on today's frontier: nothing is both smarter and cheaper.
- Grok 4.5 (High) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
GPT-6 Luna (Medium)Grok 4.5 (High)Today's Pareto frontierEvery other model
Matchup
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Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/gpt-6-luna-medium/grok-4-5 · Markdown: /api/v1/compare/gpt-6-luna-medium/grok-4-5?format=md · llms.txt · agent skill