Claude Fable 5.1 (Medium, Default Fallback) vs GPT-5.5 Instant (June 2026)
Which is better for the money: Claude Fable 5.1 (Medium, Default Fallback) by Anthropic or GPT-5.5 Instant (June 2026) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-27.
Depends on your budget
Claude Fable 5.1 (Medium, Default Fallb… scores 22.9 points higher (48.9 vs 26.0) but costs 4.0× as much to run the benchmark ($3983 vs $987; flagship vs premium cost classes). They are not alternatives at one budget: pick Claude Fable 5.1 (Medium, Default Fallb… when you need intelligence above 26.0, and GPT-5.5 Instant (June 2026) when 26.0 is enough.
| Metric | Claude Fable 5.1 (Medium, Default Fallback) | GPT-5.5 Instant (June 2026) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 48.9 | 26.0 | −46.8% GPT-5.5 Instant (June… is 46.8% less intelligent |
| Total AA cost (lower is better) | $3,983.28 | $986.85 | −75.2% GPT-5.5 Instant (June… is 75.2% cheaper |
| End-to-end time (lower is better) | 22.02s | 16.20s | −26.4% GPT-5.5 Instant (June… is 26.4% faster |
| Price per 1M tokens (in / out) | $10.0 / $50.0 | $5.00 / $30.0 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.5 Instant (June 2026) vs Claude Fable 5.1 (Medium, Default Fallback): 46.8% less intelligence, 75.2% less cost to run the AA benchmark, and 26.4% faster end-to-end.
Against the frontier
- Claude Fable 5.1 (Medium, Default Fallback) is off the frontier: at the same or lower cost, Kimi K3.1 Pro scores 55.10 for $3117.
- GPT-5.5 Instant (June 2026) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Xhigh) scores 51.00 for $662.
Compare something else
Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-fable-5-1-medium/gpt-5-5-instant-06-26 · Markdown: /api/v1/compare/claude-fable-5-1-medium/gpt-5-5-instant-06-26?format=md · llms.txt · agent skill