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

GPT-5.5-Pro vs GLM-4

OpenAI
GPT-5.5-Pro
Z.ai
GLM-4
Overview
CompanyOpenAIZ.ai
Release dateApr 23 2026Jan 16 2024
AccessProprietaryProprietary
Benchmarks
Nonsense detection
BullshitBench v2
36%
Web browsing
BrowseComp
90.1%
Advanced math
FrontierMath · Tier 1–3
52.4%
Advanced math
FrontierMath · Tier 4
39.6%
Knowledge work
GDPval (win/tie rate)
82.3%
Timeline
Release gapGLM-4 shipped 828 days before GPT-5.5-Pro

Which is better: GPT-5.5-Pro or GLM-4?

GPT-5.5-Pro and GLM-4 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. GLM-4 shipped 828 days before GPT-5.5-Pro, so benchmark comparisons should account for the intervening progress.

Published specifications for these two models are limited — see each model page for the latest details.

Direct benchmark comparisons are unavailable — GPT-5.5-Pro and GLM-4 don't publish scores on any of the same benchmarks.

Frequently asked questions

GPT-5.5-Pro was released by OpenAI on Apr 23 2026.

GLM-4 was released by Z.ai on Jan 16 2024.

Other comparisons