Claude Opus 5.5 (High, Default Fallback) vs GLM-5.3-Flash
Which is better for the money: Claude Opus 5.5 (High, Default Fallback) by Anthropic or GLM-5.3-Flash by Z AI? 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
Claude Opus 5.5 (High, Default Fallback) scores 11.8 points higher (53.6 vs 41.8) but costs 7.1× as much to run the benchmark ($2172 vs $306; flagship vs mid-range cost classes). They are not alternatives at one budget: pick Claude Opus 5.5 (High, Default Fallback) when you need intelligence above 41.8, and GLM-5.3-Flash when 41.8 is enough.
| Metric | Claude Opus 5.5 (High, Default Fallback) | GLM-5.3-Flash | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 53.6 | 41.8 | −22.0% GLM-5.3-Flash is 22.0% less intelligent |
| Total AA cost (lower is better) | $2,172.43 | $305.52 | −85.9% GLM-5.3-Flash is 85.9% cheaper |
| End-to-end time (lower is better) | 33.81s | 39.33s | +16.3% GLM-5.3-Flash is 16.3% slower |
| Price per 1M tokens (in / out) | $4.00 / $20.0 | $0.15 / $0.50 | |
| Input modalities | Text, Image | Text, Image |
GLM-5.3-Flash vs Claude Opus 5.5 (High, Default Fallback): 22.0% less intelligence, 85.9% less cost to run the AA benchmark, and 16.3% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Opus 5.5 (High, Default Fallback) is on today's frontier: nothing is both smarter and cheaper.
- GLM-5.3-Flash is off the frontier: at the same or lower cost, MiMo-V2.6-Pro scores 46.30 for $207.
Claude Opus 5.5 (High, Default Fallback)GLM-5.3-FlashToday's Pareto frontierOpen-weights frontierEvery other model
Matchup
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