AI Model Release Tracker - Timeline of Major AI Models from 2022-2026

Claude 3.5 Sonnet vs GLM-5.1

Anthropic
Claude 3.5 Sonnet
Z.ai
GLM-5.1
Overview
CompanyAnthropicZ.ai
Release dateJun 20 2024Apr 7 2026
AccessProprietaryOpen Weight
Specifications
Parameters
744B
Context window
200k
Benchmarks
Nonsense detection
BullshitBench v2
45%
Coding
SWE-Bench Verified
33.4%
Agentic terminal coding
Terminal-Bench 2.0
63.5%
Web browsing
BrowseComp
68%
Science
GPQA Diamond
59.4%
86.2%Best
Timeline
Release gapClaude 3.5 Sonnet shipped 656 days before GLM-5.1

Which is better: Claude 3.5 Sonnet or GLM-5.1?

GLM-5.1 leads Claude 3.5 Sonnet on 1 of the 1 benchmark they both report (GPQA Diamond). Claude 3.5 Sonnet shipped 656 days before GLM-5.1, so benchmark comparisons should account for the intervening progress.

Claude 3.5 Sonnet is proprietary, while GLM-5.1 is open weight.

On GPQA Diamond, GLM-5.1 leads at 86.2% vs Claude 3.5 Sonnet at 59.4%.

Frequently asked questions

Claude 3.5 Sonnet was released by Anthropic on Jun 20 2024.

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

GLM-5.1 leads on GPQA Diamond — Claude 3.5 Sonnet 59.4% vs GLM-5.1 86.2%.

Claude 3.5 Sonnet is a proprietary model released by Anthropic. GLM-5.1 is an open weight model released by Z.ai.

Other comparisons