Claude Sonnet 5.5 (Max, Default Fallback) vs GLM-5.1 (Reasoning)

Which is better for the money: Claude Sonnet 5.5 (Max, Default Fallback) 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

AnthropicClaude Sonnet 5.5 (Max, Default Fallback)Off the frontier

Intelligence: 56.00
Total cost: $7260

Z AIGLM-5.1 (Reasoning)Off the frontier

Intelligence: 26.10
Total cost: $1487

Verdict

Depends on your budget

Claude Sonnet 5.5 (Max, Default Fallbac… scores 29.9 points higher (56.0 vs 26.1) but costs 4.9× as much to run the benchmark ($7260 vs $1487; flagship vs premium cost classes). They are not alternatives at one budget: pick Claude Sonnet 5.5 (Max, Default Fallbac… when you need intelligence above 26.1, and GLM-5.1 (Reasoning) when 26.1 is enough.

Metric	Claude Sonnet 5.5 (Max, Default Fallback)	GLM-5.1 (Reasoning)	Difference
Intelligence (higher is better)	56.0	26.1	−53.4% GLM-5.1 (Reasoning) is 53.4% less intelligent
Total AA cost (lower is better)	$7,259.50	$1,486.78	−79.5% GLM-5.1 (Reasoning) is 79.5% cheaper
End-to-end time (lower is better)	367.63s	60.66s	−83.5% GLM-5.1 (Reasoning) is 83.5% faster
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 5.5 (Max, Default Fallback): 53.4% less intelligence, 79.5% less cost to run the AA benchmark, and 83.5% faster end-to-end.

Open this matchup in the interactive picker Claude Sonnet 5.5 (Max, Default Fallback): what beats it GLM-5.1 (Reasoning): what beats it

Today's Pareto frontier

Against the frontier

Claude Sonnet 5.5 (Max, Default Fallback) 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 Sonnet 5.5 (Max, Default Fallback)GLM-5.1 (Reasoning)Today's Pareto frontierOpen-weights frontierEvery other model

Matchup

Compare something else

Agents: Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-sonnet-5-5/glm-5-1 · Markdown: /api/v1/compare/claude-sonnet-5-5/glm-5-1?format=md · llms.txt · agent skill