Gemini 3.8 Flash (Medium) vs GPT-5.6 Luna (Medium)
Which is better for the money: Gemini 3.8 Flash (Medium) by Google or GPT-5.6 Luna (Medium) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-25.
Trade-off
Verdict
Depends on your budget
Gemini 3.8 Flash (Medium) scores 14.8 points higher (39.8 vs 25.0) but costs 25× as much to run the benchmark ($1100 vs $44.3; premium vs budget cost classes). They are not alternatives at one budget: pick Gemini 3.8 Flash (Medium) when you need intelligence above 25.0, and GPT-5.6 Luna (Medium) when 25.0 is enough.
| Metric | Gemini 3.8 Flash (Medium) | GPT-5.6 Luna (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 39.8 | 25.0 | −37.2% GPT-5.6 Luna (Medium) is 37.2% less intelligent |
| Total AA cost (lower is better) | $1,100.06 | $44.32 | −96.0% GPT-5.6 Luna (Medium) is 96.0% cheaper |
| End-to-end time (lower is better) | Not reported | 6.11s | — not comparable |
| Price per 1M tokens (in / out) | $0.75 / $3.75 | $0.20 / $1.20 | |
| Input modalities | Text, Image, Speech, Video | Text, Image |
GPT-5.6 Luna (Medium) vs Gemini 3.8 Flash (Medium): 37.2% less intelligence, 96.0% less cost to run the AA benchmark, and end-to-end time not fully reported.
Today's Pareto frontier
Against the frontier
- Gemini 3.8 Flash (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) is off the frontier: at the same or lower cost, GPT-6 Luna (Medium) scores 29.90 for $31.2.
Gemini 3.8 Flash (Medium)GPT-5.6 Luna (Medium)Today's Pareto frontierEvery other model
Matchup
Compare something else
Agents:
Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/gemini-3-8-flash-medium/gpt-5-6-luna-medium · Markdown: /api/v1/compare/gemini-3-8-flash-medium/gpt-5-6-luna-medium?format=md · llms.txt · agent skill