Claude Sonnet 5.5 (Medium, Default Fallback) vs LongCat 2.0
Which is better for the money: Claude Sonnet 5.5 (Medium, Default Fallback) by Anthropic or LongCat 2.0 by LongCat? 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 21.7 points higher (40.8 vs 19.1) but costs 1.1× as much to run the benchmark ($622 vs $545; both premium class). Pick Claude Sonnet 5.5 (Medium, Default Fall… when the extra intelligence is worth the premium, otherwise LongCat 2.0.
| Metric | Claude Sonnet 5.5 (Medium, Default Fallback) | LongCat 2.0 | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 40.8 | 19.1 | −53.2% LongCat 2.0 is 53.2% less intelligent |
| Total AA cost (lower is better) | $622.28 | $544.74 | −12.5% LongCat 2.0 is 12.5% cheaper |
| End-to-end time (lower is better) | 5.98s | 35.69s | +496.8% LongCat 2.0 is 496.8% slower |
| Price per 1M tokens (in / out) | $2.00 / $10.0 | $0.75 / $2.95 | |
| Input modalities | Text, Image | Text |
LongCat 2.0 vs Claude Sonnet 5.5 (Medium, Default Fallback): 53.2% less intelligence, 12.5% less cost to run the AA benchmark, and 496.8% 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.
- LongCat 2.0 is off the frontier: at the same or lower cost, GPT-6.1 Sol (High) scores 50.20 for $521.
Claude Sonnet 5.5 (Medium, Default Fallback)LongCat 2.0Today's Pareto frontierOpen-weights frontierEvery other model
Matchup
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