Gemini 3.5 Flash (High) vs GLM-5.1 (Reasoning)
Which is better for the money: Gemini 3.5 Flash (High) by Google 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
Gemini 3.5 Flash (High) scores 6.5 points higher (32.6 vs 26.1) but costs 2.8× as much to run the benchmark ($4222 vs $1487; flagship vs premium cost classes). Pick Gemini 3.5 Flash (High) when the extra intelligence is worth the premium, otherwise GLM-5.1 (Reasoning).
| Metric | Gemini 3.5 Flash (High) | GLM-5.1 (Reasoning) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 32.6 | 26.1 | −19.9% GLM-5.1 (Reasoning) is 19.9% less intelligent |
| Total AA cost (lower is better) | $4,222.12 | $1,486.78 | −64.8% GLM-5.1 (Reasoning) is 64.8% cheaper |
| End-to-end time (lower is better) | 16.46s | 60.66s | +268.5% GLM-5.1 (Reasoning) is 268.5% slower |
| Price per 1M tokens (in / out) | $1.50 / $9.00 | $1.28 / $4.07 | |
| Input modalities | Text, Image, Speech, Video | Text |
GLM-5.1 (Reasoning) vs Gemini 3.5 Flash (High): 19.9% less intelligence, 64.8% less cost to run the AA benchmark, and 268.5% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Gemini 3.5 Flash (High) 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.
Gemini 3.5 Flash (High)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/gemini-3-5-flash/glm-5-1 · Markdown: /api/v1/compare/gemini-3-5-flash/glm-5-1?format=md · llms.txt · agent skill