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

GPT-5.5-Pro vs GLM-5.2

OpenAI
GPT-5.5-Pro
Z.ai
GLM-5.2
Overview
CompanyOpenAIZ.ai
Release dateApr 23 2026Jun 16 2026
AccessProprietaryOpen Weight
Specifications
Parameters
744B
Context window
1M
Benchmarks
Nonsense detection
BullshitBench v2
36%
Agentic coding
SWE-Bench Pro
62.1%
Agentic terminal coding
Terminal-Bench 2.1
81%
Web browsing
BrowseComp
90.1%
Multidisciplinary reasoning
Humanity's Last Exam · no tools
40.5%
Advanced math
FrontierMath · Tier 1–3
52.4%
Advanced math
FrontierMath · Tier 4
39.6%
Science
GPQA Diamond
91.2%
Knowledge work
GDPval (win/tie rate)
82.3%
Timeline
Release gapGPT-5.5-Pro shipped 54 days before GLM-5.2

Which is better: GPT-5.5-Pro or GLM-5.2?

GPT-5.5-Pro and GLM-5.2 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. GPT-5.5-Pro shipped 54 days before GLM-5.2, so benchmark comparisons should account for the intervening progress.

GPT-5.5-Pro is proprietary, while GLM-5.2 is open weight.

Direct benchmark comparisons are unavailable — GPT-5.5-Pro and GLM-5.2 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-5.2 was released by Z.ai on Jun 16 2026.

GPT-5.5-Pro is a proprietary model released by OpenAI. GLM-5.2 is an open weight model released by Z.ai.

Other comparisons