Claude Opus 4.8 (Max) vs GLM-5.1 (Reasoning)
Which is better for the money: Claude Opus 4.8 (Max) by Anthropic or GLM-5.1 (Reasoning) 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 4.8 (Max) scores 15.7 points higher (41.8 vs 26.1) but costs 4.6× as much to run the benchmark ($6874 vs $1487; flagship vs premium cost classes). They are not alternatives at one budget: pick Claude Opus 4.8 (Max) when you need intelligence above 26.1, and GLM-5.1 (Reasoning) when 26.1 is enough.
| Metric | Claude Opus 4.8 (Max) | GLM-5.1 (Reasoning) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 41.8 | 26.1 | −37.6% GLM-5.1 (Reasoning) is 37.6% less intelligent |
| Total AA cost (lower is better) | $6,873.86 | $1,486.78 | −78.4% GLM-5.1 (Reasoning) is 78.4% cheaper |
| End-to-end time (lower is better) | 37.90s | 60.66s | +60.1% GLM-5.1 (Reasoning) is 60.1% slower |
| Price per 1M tokens (in / out) | $5.00 / $25.0 | $1.28 / $4.07 | |
| Input modalities | Text, Image | Text |
GLM-5.1 (Reasoning) vs Claude Opus 4.8 (Max): 37.6% less intelligence, 78.4% less cost to run the AA benchmark, and 60.1% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Opus 4.8 (Max) is off the frontier: at the same or lower cost, Claude Opus 5.5 (Xhigh, Default Fallback) scores 56.00 for $4057.
- GLM-5.1 (Reasoning) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
Claude Opus 4.8 (Max)GLM-5.1 (Reasoning)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/claude-opus-4-8/glm-5-1 · Markdown: /api/v1/compare/claude-opus-4-8/glm-5-1?format=md · llms.txt · agent skill