modelgrep

Anthropic: Claude Sonnet 5 vs Z.ai: GLM 5.1

anthropic logoAnthropic: Claude Sonnet 5anthropic/claude-sonnet-5VSz-ai logoZ.ai: GLM 5.1z-ai/glm-5.1

Anthropic: Claude Sonnet 5 wins on more metrics (5 of 9), but the right pick depends on what you optimize for — see the breakdown below.

MetricAnthropic: Claude Sonnet 5Z.ai: GLM 5.1
Intelligence Index53.4✓40.2
Coding Index71.5✓55.8
GPQA Diamond91%✓87%
Design Arena Elo1330✓—
Speed (tokens/sec)73101✓
Latency2.5s304ms✓
Input price /M$2.00$0.966✓
Output price /M$10.00$3.04✓
Context window1M✓203K
CapabilitiesReasoningToolsJSONVisionReasoningToolsJSON
Anthropic: Claude Sonnet 5 details →Z.ai: GLM 5.1 details →