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

GPT-5.3-Codex-Spark vs GLM-5.1

OpenAI
GPT-5.3-Codex-Spark
Z.ai
GLM-5.1
Overview
CompanyOpenAIZ.ai
Release dateFeb 12 2026Apr 7 2026
AccessProprietaryOpen Weight
Specifications
Parameters
744B
Context window
128k
200k
Benchmarks
Agentic terminal coding
Terminal-Bench 2.0
63.5%
Web browsing
BrowseComp
68%
Science
GPQA Diamond
86.2%
Timeline
Release gapGPT-5.3-Codex-Spark shipped 54 days before GLM-5.1

Which is better: GPT-5.3-Codex-Spark or GLM-5.1?

GPT-5.3-Codex-Spark and GLM-5.1 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. GPT-5.3-Codex-Spark shipped 54 days before GLM-5.1, so benchmark comparisons should account for the intervening progress.

Context windows are 128k (GPT-5.3-Codex-Spark) vs 200k (GLM-5.1). GPT-5.3-Codex-Spark is proprietary, while GLM-5.1 is open weight.

Direct benchmark comparisons are unavailable — GPT-5.3-Codex-Spark and GLM-5.1 don't publish scores on any of the same benchmarks.

Frequently asked questions

GPT-5.3-Codex-Spark was released by OpenAI on Feb 12 2026.

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

GPT-5.3-Codex-Spark has a 128k context window; GLM-5.1 has 200k.

GPT-5.3-Codex-Spark is a proprietary model released by OpenAI. GLM-5.1 is an open weight model released by Z.ai.

Other comparisons