Claude Sonnet 5.5 (Medium, Default Fallback) vs gpt-oss-20b (High)
Which is better for the money: Claude Sonnet 5.5 (Medium, Default Fallback) by Anthropic or gpt-oss-20b (High) 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
Claude Sonnet 5.5 (Medium, Default Fall… scores 31.8 points higher (40.8 vs 9.0) but costs 22× as much to run the benchmark ($622 vs $28.8; premium vs budget cost classes). They are not alternatives at one budget: pick Claude Sonnet 5.5 (Medium, Default Fall… when you need intelligence above 9.0, and gpt-oss-20b (High) when 9.0 is enough.
| Metric | Claude Sonnet 5.5 (Medium, Default Fallback) | gpt-oss-20b (High) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 40.8 | 9.0 | −77.9% gpt-oss-20b (High) is 77.9% less intelligent |
| Total AA cost (lower is better) | $622.28 | $28.81 | −95.4% gpt-oss-20b (High) is 95.4% cheaper |
| End-to-end time (lower is better) | 6.20s | 15.23s | +145.6% gpt-oss-20b (High) is 145.6% slower |
| Price per 1M tokens (in / out) | $2.00 / $10.0 | $0.05 / $0.22 | |
| Input modalities | Text, Image | Text |
gpt-oss-20b (High) vs Claude Sonnet 5.5 (Medium, Default Fallback): 77.9% less intelligence, 95.4% less cost to run the AA benchmark, and 145.6% slower end-to-end.
Today's Pareto frontier
Against the frontier
- 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.
- gpt-oss-20b (High) is off the frontier: at the same or lower cost, GPT-6 Luna (Low) scores 21.50 for $10.6.
Claude Sonnet 5.5 (Medium, Default Fallback)gpt-oss-20b (High)Today's Pareto frontierOpen-weights frontierEvery other model
Matchup
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