Claude Fable 5.2 (Medium, Default Fallback) vs GPT-5.6 Luna (Max)
Which is better for the money: Claude Fable 5.2 (Medium, Default Fallback) by Anthropic or GPT-5.6 Luna (Max) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-11-10.
Trade-off
Verdict
Depends on your budget
Claude Fable 5.2 (Medium, Default Fallb… scores 32.6 points higher (56.4 vs 23.8) but costs 10× as much to run the benchmark ($3360 vs $334; flagship vs mid-range cost classes). They are not alternatives at one budget: pick Claude Fable 5.2 (Medium, Default Fallb… when you need intelligence above 23.8, and GPT-5.6 Luna (Max) when 23.8 is enough.
| Metric | Claude Fable 5.2 (Medium, Default Fallback) | GPT-5.6 Luna (Max) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 56.4 | 23.8 | −57.8% GPT-5.6 Luna (Max) is 57.8% less intelligent |
| Total AA cost (lower is better) | $3,359.66 | $334.35 | −90.0% GPT-5.6 Luna (Max) is 90.0% cheaper |
| End-to-end time (lower is better) | 27.53s | 132.39s | +380.9% GPT-5.6 Luna (Max) is 380.9% slower |
| Price per 1M tokens (in / out) | $8.00 / $40.0 | $0.20 / $1.20 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.6 Luna (Max) vs Claude Fable 5.2 (Medium, Default Fallback): 57.8% less intelligence, 90.0% less cost to run the AA benchmark, and 380.9% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Fable 5.2 (Medium, Default Fallback) is on today's frontier: nothing is both smarter and cheaper.
- GPT-5.6 Luna (Max) is off the frontier: at the same or lower cost, GPT-6.1 Terra (High) scores 42.40 for $267.
Claude Fable 5.2 (Medium, Default Fallback)GPT-5.6 Luna (Max)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/claude-fable-5-2-medium/gpt-5-6-luna · Markdown: /api/v1/compare/claude-fable-5-2-medium/gpt-5-6-luna?format=md · llms.txt · agent skill