Claude Sonnet 5 (Low) vs GLM-5.1 (Reasoning)
Which is better for the money: Claude Sonnet 5 (Low) 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
GLM-5.1 (Reasoning) scores 1.8 points higher (26.1 vs 24.3) but costs 2.3× as much to run the benchmark ($1487 vs $653; both premium class). Pick GLM-5.1 (Reasoning) when the extra intelligence is worth the premium, otherwise Claude Sonnet 5 (Low).
| Metric | Claude Sonnet 5 (Low) | GLM-5.1 (Reasoning) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 24.3 | 26.1 | +7.4% GLM-5.1 (Reasoning) is 7.4% more intelligent |
| Total AA cost (lower is better) | $652.70 | $1,486.78 | +127.8% GLM-5.1 (Reasoning) is 2.3× more expensive |
| End-to-end time (lower is better) | 8.35s | 60.66s | +626.5% GLM-5.1 (Reasoning) is 626.5% slower |
| Price per 1M tokens (in / out) | $2.00 / $10.0 | $1.28 / $4.07 | |
| Input modalities | Text, Image | Text |
GLM-5.1 (Reasoning) vs Claude Sonnet 5 (Low): 7.4% more intelligence, 127.8% more cost to run the AA benchmark, and 626.5% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Sonnet 5 (Low) is off the frontier: at the same or lower cost, GPT-6.1 Sol (High) scores 50.20 for $521.
- 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 Sonnet 5 (Low)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-sonnet-5-low/glm-5-1 · Markdown: /api/v1/compare/claude-sonnet-5-low/glm-5-1?format=md · llms.txt · agent skill