GPT-5.6 Luna (Low) vs Grok 4.3 (High)
Which is better for the money: GPT-5.6 Luna (Low) by OpenAI or Grok 4.3 (High) by SpaceXAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-26.
Trade-off
Verdict
Depends on your budget
Grok 4.3 (High) scores 3.9 points higher (24.9 vs 21.0) but costs 13× as much to run the benchmark ($363 vs $27.0; mid-range vs budget cost classes). They are not alternatives at one budget: pick Grok 4.3 (High) when you need intelligence above 21.0, and GPT-5.6 Luna (Low) when 21.0 is enough.
| Metric | GPT-5.6 Luna (Low) | Grok 4.3 (High) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 21.0 | 24.9 | +18.6% Grok 4.3 (High) is 18.6% more intelligent |
| Total AA cost (lower is better) | $27.02 | $363.24 | +1244.3% Grok 4.3 (High) is 13× more expensive |
| End-to-end time (lower is better) | 5.84s | 32.40s | +454.8% Grok 4.3 (High) is 454.8% slower |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $1.25 / $2.50 | |
| Input modalities | Text, Image | Text, Image |
Grok 4.3 (High) vs GPT-5.6 Luna (Low): 18.6% more intelligence, 1244.3% more cost to run the AA benchmark, and 454.8% slower end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.6 Luna (Low) is off the frontier: at the same or lower cost, GPT-6 Luna (Low) scores 21.50 for $10.6.
- Grok 4.3 (High) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Medium) scores 47.80 for $361.
GPT-5.6 Luna (Low)Grok 4.3 (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-5-6-luna-low/grok-4-3 · Markdown: /api/v1/compare/gpt-5-6-luna-low/grok-4-3?format=md · llms.txt · agent skill