Claude 2.1vsGLM-5.1

Claude 2.1
GLM-5.1
Specifications
Parameters
744B
Context window
200k
200k
Benchmarks
Nonsense detection
BullshitBench v2
22%
Next.js coding
Next.js Evals
75%
Agentic terminal coding
Terminal-Bench 2.0
63.5%
Web browsing
BrowseComp
68%
Multidisciplinary reasoning
Humanity's Last Exam · with tools
52.3%
Science
GPQA Diamond
86.2%
Community preference (code)
Arena Elo (Code)
1518
Overview
CompanyAnthropicZ.ai
Release dateNov 21 2023Apr 7 2026
AccessProprietaryOpen Weight

Which is better: Claude 2.1 or GLM-5.1?

Claude 2.1 and GLM-5.1 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Claude 2.1 shipped 868 days before GLM-5.1, so benchmark comparisons should account for the intervening progress.

Context windows are 200k (Claude 2.1) vs 200k (GLM-5.1). Claude 2.1 is proprietary, while GLM-5.1 is open weight.

Direct benchmark comparisons are unavailable — Claude 2.1 and GLM-5.1 don't publish scores on any of the same benchmarks.

Frequently asked questions

Claude 2.1 was released by Anthropic on Nov 21 2023.

GLM-5.1 was released by Z.ai on Apr 7 2026.

Claude 2.1 has a 200k context window; GLM-5.1 has 200k.

Claude 2.1 is a proprietary model released by Anthropic. GLM-5.1 is an open weight model released by Z.ai.

Other comparisons