Claude Opus 5.5 (Low, Default Fallback) vs Claude Opus 5 (Medium)
Which is better for the money: Claude Opus 5.5 (Low, Default Fallback) by Anthropic or Claude Opus 5 (Medium) by Anthropic? 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
Claude Opus 5 (Medium) scores 2.5 points higher (44.8 vs 42.3) but costs 3.2× as much to run the benchmark ($2732 vs $860; flagship vs premium cost classes). They are not alternatives at one budget: pick Claude Opus 5 (Medium) when you need intelligence above 42.3, and Claude Opus 5.5 (Low, Default Fallback) when 42.3 is enough.
| Metric | Claude Opus 5.5 (Low, Default Fallback) | Claude Opus 5 (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 42.3 | 44.8 | +5.9% Claude Opus 5 (Medium) is 5.9% more intelligent |
| Total AA cost (lower is better) | $860.33 | $2,731.91 | +217.5% Claude Opus 5 (Medium) is 3.2× more expensive |
| End-to-end time (lower is better) | 11.16s | 12.85s | +15.1% Claude Opus 5 (Medium) is 15.1% slower |
| Price per 1M tokens (in / out) | $4.00 / $20.0 | $5.00 / $25.0 | |
| Input modalities | Text, Image | Text, Image |
Claude Opus 5 (Medium) vs Claude Opus 5.5 (Low, Default Fallback): 5.9% more intelligence, 217.5% more cost to run the AA benchmark, and 15.1% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Opus 5.5 (Low, Default Fallback) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Xhigh) scores 51.00 for $662.
- Claude Opus 5 (Medium) is off the frontier: at the same or lower cost, Claude Opus 5.5 (High, Default Fallback) scores 53.60 for $2172.
Claude Opus 5.5 (Low, Default Fallback)Claude Opus 5 (Medium)Today's Pareto frontierEvery other model
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