Claude Opus 5.5 (Low, Default Fallback) vs GLM-5.3-Flash
Which is better for the money: Claude Opus 5.5 (Low, 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 (Low, Default Fallback) scores 0.5 points higher (42.3 vs 41.8) but costs 2.8× as much to run the benchmark ($860 vs $306; premium vs mid-range cost classes). Pick Claude Opus 5.5 (Low, Default Fallback) when the extra intelligence is worth the premium, otherwise GLM-5.3-Flash.
| Metric | Claude Opus 5.5 (Low, Default Fallback) | GLM-5.3-Flash | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 42.3 | 41.8 | −1.2% GLM-5.3-Flash is 1.2% less intelligent |
| Total AA cost (lower is better) | $860.33 | $305.52 | −64.5% GLM-5.3-Flash is 64.5% cheaper |
| End-to-end time (lower is better) | 12.48s | 38.43s | +207.9% GLM-5.3-Flash is 207.9% 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 (Low, Default Fallback): 1.2% less intelligence, 64.5% less cost to run the AA benchmark, and 207.9% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Opus 5.5 (Low, Default Fallback) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Xhigh) scores 51.00 for $662.
- 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 (Low, Default Fallback)GLM-5.3-FlashToday's Pareto frontierOpen-weights frontierEvery other model
Matchup
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