GPT-5.6 Luna (Xhigh) vs Mistral Small 4 (Reasoning)
Which is better for the money: GPT-5.6 Luna (Xhigh) by OpenAI or Mistral Small 4 (Reasoning) by Mistral? 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
GPT-5.6 Luna (Xhigh) scores 23.3 points higher (34.6 vs 11.3) but costs 4.2× as much to run the benchmark ($179 vs $42.5; mid-range vs budget cost classes). They are not alternatives at one budget: pick GPT-5.6 Luna (Xhigh) when you need intelligence above 11.3, and Mistral Small 4 (Reasoning) when 11.3 is enough.
| Metric | GPT-5.6 Luna (Xhigh) | Mistral Small 4 (Reasoning) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 34.6 | 11.3 | −67.3% Mistral Small 4 (Reas… is 67.3% less intelligent |
| Total AA cost (lower is better) | $179.33 | $42.50 | −76.3% Mistral Small 4 (Reas… is 76.3% cheaper |
| End-to-end time (lower is better) | 30.83s | 14.50s | −53.0% Mistral Small 4 (Reas… is 53.0% faster |
| Price per 1M tokens (in / out) | $0.20 / $1.20 | $0.15 / $0.60 | |
| Input modalities | Text, Image | Text, Image |
Mistral Small 4 (Reasoning) vs GPT-5.6 Luna (Xhigh): 67.3% less intelligence, 76.3% less cost to run the AA benchmark, and 53.0% faster end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.6 Luna (Xhigh) is off the frontier: at the same or lower cost, Claude Haiku 5.5 (Xhigh) scores 41.20 for $158.
- Mistral Small 4 (Reasoning) is off the frontier: at the same or lower cost, GPT-6 Luna (Medium) scores 29.90 for $31.2.
GPT-5.6 Luna (Xhigh)Mistral Small 4 (Reasoning)Today's Pareto frontierOpen-weights 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-xhigh/mistral-small-4 · Markdown: /api/v1/compare/gpt-5-6-luna-xhigh/mistral-small-4?format=md · llms.txt · agent skill