Claude Sonnet 5.5 (Xhigh, Default Fallback) vs Kimi K3.1 Pro
Which is better for the money: Claude Sonnet 5.5 (Xhigh, Default Fallback) by Anthropic or Kimi K3.1 Pro by Kimi? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-24.
Trade-off
Verdict
Depends on your budget
Kimi K3.1 Pro scores 3.2 points higher (55.1 vs 51.9) but costs 1.4× as much to run the benchmark ($3117 vs $2177; both flagship class). Pick Kimi K3.1 Pro when the extra intelligence is worth the premium, otherwise Claude Sonnet 5.5 (Xhigh, Default Fallb….
| Metric | Claude Sonnet 5.5 (Xhigh, Default Fallback) | Kimi K3.1 Pro | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 51.9 | 55.1 | +6.2% Kimi K3.1 Pro is 6.2% more intelligent |
| Total AA cost (lower is better) | $2,176.82 | $3,117.31 | +43.2% Kimi K3.1 Pro is 43.2% more expensive |
| End-to-end time (lower is better) | 32.10s | 42.64s | +32.8% Kimi K3.1 Pro is 32.8% slower |
| Price per 1M tokens (in / out) | $2.00 / $10.0 | $2.00 / $10.0 | |
| Input modalities | Text, Image | Text, Image |
Kimi K3.1 Pro vs Claude Sonnet 5.5 (Xhigh, Default Fallback): 6.2% more intelligence, 43.2% more cost to run the AA benchmark, and 32.8% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Sonnet 5.5 (Xhigh, Default Fallback) is off the frontier: at the same or lower cost, Claude Opus 5.5 (High, Default Fallback) scores 53.60 for $2172.
- Kimi K3.1 Pro is on today's frontier: nothing is both smarter and cheaper.
Claude Sonnet 5.5 (Xhigh, Default Fallback)Kimi K3.1 ProToday's Pareto frontierEvery other model
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