GLM-5.3 (Low) vs GPT-5.6 Luna (Medium)
Which is better for the money: GLM-5.3 (Low) by Z AI or GPT-5.6 Luna (Medium) by OpenAI? 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
GLM-5.3 (Low) scores 9.3 points higher (34.3 vs 25.0) but costs 23× as much to run the benchmark ($1013 vs $44.3; premium vs budget cost classes). They are not alternatives at one budget: pick GLM-5.3 (Low) when you need intelligence above 25.0, and GPT-5.6 Luna (Medium) when 25.0 is enough.
| Metric | GLM-5.3 (Low) | GPT-5.6 Luna (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 34.3 | 25.0 | −27.1% GPT-5.6 Luna (Medium) is 27.1% less intelligent |
| Total AA cost (lower is better) | $1,012.50 | $44.32 | −95.6% GPT-5.6 Luna (Medium) is 95.6% cheaper |
| End-to-end time (lower is better) | 31.21s | 5.82s | −81.4% GPT-5.6 Luna (Medium) is 81.4% faster |
| Price per 1M tokens (in / out) | $1.40 / $4.40 | $0.20 / $1.20 | |
| Input modalities | Text | Text, Image |
GPT-5.6 Luna (Medium) vs GLM-5.3 (Low): 27.1% less intelligence, 95.6% less cost to run the AA benchmark, and 81.4% faster end-to-end.
Today's Pareto frontier
Against the frontier
- GLM-5.3 (Low) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Xhigh) scores 51.00 for $662.
- GPT-5.6 Luna (Medium) is off the frontier: at the same or lower cost, GPT-6 Luna (Medium) scores 29.90 for $31.2.
GLM-5.3 (Low)GPT-5.6 Luna (Medium)Today's Pareto frontierOpen-weights frontierEvery other model
Matchup
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Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/glm-5-3-low/gpt-5-6-luna-medium · Markdown: /api/v1/compare/glm-5-3-low/gpt-5-6-luna-medium?format=md · llms.txt · agent skill