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

Grok 4 Fast vs GLM-5.2

xAI
Grok 4 Fast
Z.ai
GLM-5.2
Overview
CompanyxAIZ.ai
Release dateSep 2025Jun 16 2026
AccessProprietaryOpen Weight
Specifications
Parameters
744B
Context window
1M
Benchmarks
Agentic coding
SWE-Bench Pro
62.1%
Agentic terminal coding
Terminal-Bench 2.1
81%
Multidisciplinary reasoning
Humanity's Last Exam · no tools
40.5%
Science
GPQA Diamond
91.2%
Timeline
Release gapGrok 4 Fast shipped 288 days before GLM-5.2

Which is better: Grok 4 Fast or GLM-5.2?

Grok 4 Fast and GLM-5.2 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Grok 4 Fast shipped 288 days before GLM-5.2, so benchmark comparisons should account for the intervening progress.

Grok 4 Fast is proprietary, while GLM-5.2 is open weight.

Direct benchmark comparisons are unavailable — Grok 4 Fast and GLM-5.2 don't publish scores on any of the same benchmarks.

Frequently asked questions

Grok 4 Fast was released by xAI on Sep 2025.

GLM-5.2 was released by Z.ai on Jun 16 2026.

Grok 4 Fast is a proprietary model released by xAI. GLM-5.2 is an open weight model released by Z.ai.

Other comparisons