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

GPT-5.5 vs GLM-5.2

OpenAI
GPT-5.5
Z.ai
GLM-5.2
Overview
CompanyOpenAIZ.ai
Release dateApr 23 2026Jun 16 2026
AccessProprietaryOpen Weight
Specifications
Parameters
744B
Context window
1.05M
1M
Benchmarks
Nonsense detection
BullshitBench v2
47%
Agentic coding
SWE-Bench Pro
58.6%
62.1%Best
Multilingual coding
SWE-Bench Multilingual
77.8%
Agentic coding
CursorBench v3.1
59.2%
Agentic terminal coding
Terminal-Bench 2.1
78.2%
81%Best
Agentic terminal coding
Terminal-Bench 2.0
82.7%
Software engineering
Expert-SWE (Internal)
73.1%
Multi-step tool use
MCP Atlas
75.3%
General tool use
Toolathlon
55.6%
Web browsing
BrowseComp
84.4%
Cybersecurity
CyberGym
81.8%
Multidisciplinary reasoning
Humanity's Last Exam · no tools
41.4%Best
40.5%
Multidisciplinary reasoning
Humanity's Last Exam · with tools
52.2%
Abstract reasoning
ARC-AGI-2
84.6%
Advanced math
FrontierMath · Tier 1–3
51.7%
Advanced math
FrontierMath · Tier 4
35.4%
Science
GPQA Diamond
93.6%Best
91.2%
Agentic computer use
OSWorld-Verified
78.7%
Agentic financial analysis
Finance Agent v2
51.8%
Knowledge work
GDPval-AA
1769
Knowledge work
GDPval (win/tie rate)
84.9%
Chart reasoning
CharXiv Reasoning
84.1%
Multimodal reasoning
MMMU-Pro
81.2%
Spatial reasoning
Blueprint-Bench 2
36.2%
Long context
MRCR v2 (8-needle) · 128k average
94.8%
Timeline
Release gapGPT-5.5 shipped 54 days before GLM-5.2

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

GPT-5.5 and GLM-5.2 are evenly matched across the 4 benchmarks they both report (SWE-Bench Pro, Terminal-Bench 2.1, Humanity's Last Exam, GPQA Diamond). GPT-5.5 shipped 54 days before GLM-5.2, so benchmark comparisons should account for the intervening progress.

Context windows are 1.05M (GPT-5.5) vs 1M (GLM-5.2). GPT-5.5 is proprietary, while GLM-5.2 is open weight.

On SWE-Bench Pro, GLM-5.2 leads at 62.1% vs GPT-5.5 at 58.6%. On Terminal-Bench 2.1, GLM-5.2 leads at 81% vs GPT-5.5 at 78.2%. On Humanity's Last Exam · no tools, GPT-5.5 leads at 41.4% vs GLM-5.2 at 40.5%. On GPQA Diamond, GPT-5.5 leads at 93.6% vs GLM-5.2 at 91.2%.

Frequently asked questions

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

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

GLM-5.2 leads on SWE-Bench Pro — GPT-5.5 58.6% vs GLM-5.2 62.1%.

GPT-5.5 leads on Humanity's Last Exam · no tools — GPT-5.5 41.4% vs GLM-5.2 40.5%.

GPT-5.5 has a 1.05M context window; GLM-5.2 has 1M.

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

Other comparisons