Claude Opus 5.5 (Medium, Default Fallback) vs GLM-5.3-Flash
Which is better for the money: Claude Opus 5.5 (Medium, 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 2026-10-25.
Trade-off
Verdict
Depends on your budget
Claude Opus 5.5 (Medium, Default Fallba… scores 9.4 points higher (51.2 vs 41.8) but costs 5.3× as much to run the benchmark ($1627 vs $306; premium vs mid-range cost classes). They are not alternatives at one budget: pick Claude Opus 5.5 (Medium, Default Fallba… when you need intelligence above 41.8, and GLM-5.3-Flash when 41.8 is enough.
| Metric | Claude Opus 5.5 (Medium, Default Fallback) | GLM-5.3-Flash | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 51.2 | 41.8 | −18.4% GLM-5.3-Flash is 18.4% less intelligent |
| Total AA cost (lower is better) | $1,626.81 | $305.52 | −81.2% GLM-5.3-Flash is 81.2% cheaper |
| End-to-end time (lower is better) | 20.68s | 38.89s | +88.1% GLM-5.3-Flash is 88.1% 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 (Medium, Default Fallback): 18.4% less intelligence, 81.2% less cost to run the AA benchmark, and 88.1% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Opus 5.5 (Medium, Default Fallback) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
- 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 (Medium, Default Fallback)GLM-5.3-FlashToday's Pareto frontierOpen-weights frontierEvery other model
Matchup
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