GPT-5.6 Luna (Medium) vs Grok 4.6 (Low)
Which is better for the money: GPT-5.6 Luna (Medium) by OpenAI or Grok 4.6 (Low) 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 4.6 (Low) scores 10.1 points higher (35.1 vs 25.0) but costs 14× as much to run the benchmark ($614 vs $44.3; premium vs budget cost classes). They are not alternatives at one budget: pick Grok 4.6 (Low) when you need intelligence above 25.0, and GPT-5.6 Luna (Medium) when 25.0 is enough.
| Metric | GPT-5.6 Luna (Medium) | Grok 4.6 (Low) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 25.0 | 35.1 | +40.4% Grok 4.6 (Low) is 40.4% more intelligent |
| Total AA cost (lower is better) | $44.32 | $613.92 | +1285.2% Grok 4.6 (Low) is 14× more expensive |
| End-to-end time (lower is better) | 6.50s | 13.25s | +103.8% Grok 4.6 (Low) is 103.8% slower |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $2.00 / $6.00 | |
| Input modalities | Text, Image | Text, Image |
Grok 4.6 (Low) vs GPT-5.6 Luna (Medium): 40.4% more intelligence, 1285.2% more cost to run the AA benchmark, and 103.8% slower end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.6 Luna (Medium) is off the frontier: at the same or lower cost, GPT-6 Luna (Medium) scores 29.90 for $31.2.
- Grok 4.6 (Low) is off the frontier: at the same or lower cost, GPT-6.1 Sol (High) scores 50.20 for $521.
GPT-5.6 Luna (Medium)Grok 4.6 (Low)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-medium/grok-4-6-low · Markdown: /api/v1/compare/gpt-5-6-luna-medium/grok-4-6-low?format=md · llms.txt · agent skill