Claude Opus 5 (Xhigh) vs Claude Sonnet 5.5 (Medium, Default Fallback)
Which is better for the money: Claude Opus 5 (Xhigh) by Anthropic or Claude Sonnet 5.5 (Medium, Default Fallback) by Anthropic? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-26.
Trade-off
Verdict
Depends on your budget
Claude Opus 5 (Xhigh) scores 8.9 points higher (49.7 vs 40.8) but costs 9.4× as much to run the benchmark ($5868 vs $622; flagship vs premium cost classes). They are not alternatives at one budget: pick Claude Opus 5 (Xhigh) when you need intelligence above 40.8, and Claude Sonnet 5.5 (Medium, Default Fall… when 40.8 is enough.
| Metric | Claude Opus 5 (Xhigh) | Claude Sonnet 5.5 (Medium, Default Fallback) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 49.7 | 40.8 | −17.9% Claude Sonnet 5.5 (Me… is 17.9% less intelligent |
| Total AA cost (lower is better) | $5,867.76 | $622.28 | −89.4% Claude Sonnet 5.5 (Me… is 89.4% cheaper |
| End-to-end time (lower is better) | 35.31s | 6.15s | −82.6% Claude Sonnet 5.5 (Me… is 82.6% faster |
| Price per 1M tokens (in / out) | $5.00 / $25.0 | $2.00 / $10.0 | |
| Input modalities | Text, Image | Text, Image |
Claude Sonnet 5.5 (Medium, Default Fallback) vs Claude Opus 5 (Xhigh): 17.9% less intelligence, 89.4% less cost to run the AA benchmark, and 82.6% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Opus 5 (Xhigh) is off the frontier: at the same or lower cost, Claude Opus 5.5 (Xhigh, Default Fallback) scores 56.00 for $4057.
- Claude Sonnet 5.5 (Medium, Default Fallback) is off the frontier: at the same or lower cost, GPT-6.1 Sol (High) scores 50.20 for $521.
Claude Opus 5 (Xhigh)Claude Sonnet 5.5 (Medium, Default Fallback)Today's Pareto frontierEvery other model
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