GPT-5.6 Luna (Medium) vs Grok 4.6 (Medium)
Which is better for the money: GPT-5.6 Luna (Medium) by OpenAI or Grok 4.6 (Medium) 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 4.6 (Medium) scores 17.8 points higher (42.8 vs 25.0) but costs 35× as much to run the benchmark ($1557 vs $44.3; premium vs budget cost classes). They are not alternatives at one budget: pick Grok 4.6 (Medium) 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 (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 25.0 | 42.8 | +71.2% Grok 4.6 (Medium) is 71.2% more intelligent |
| Total AA cost (lower is better) | $44.32 | $1,557.04 | +3413.2% Grok 4.6 (Medium) is 35× more expensive |
| End-to-end time (lower is better) | 5.82s | 31.56s | +442.3% Grok 4.6 (Medium) is 442.3% slower |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $2.00 / $6.00 | |
| Input modalities | Text, Image | Text, Image |
Grok 4.6 (Medium) vs GPT-5.6 Luna (Medium): 71.2% more intelligence, 3413.2% more cost to run the AA benchmark, and 442.3% 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 (Medium) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
GPT-5.6 Luna (Medium)Grok 4.6 (Medium)Today's Pareto frontierEvery other model
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