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

GPT-4.1 nano vs GLM-5.1

OpenAI
GPT-4.1 nano
Z.ai
GLM-5.1
Overview
CompanyOpenAIZ.ai
Release dateApr 14 2025Apr 7 2026
AccessProprietaryOpen Weight
Specifications
Parameters
744B
Context window
1M
200k
Benchmarks
Nonsense detection
BullshitBench v2
22%
Next.js coding
Next.js Evals
75%
Agentic terminal coding
Terminal-Bench 2.0
63.5%
Web browsing
BrowseComp
68%
Multidisciplinary reasoning
Humanity's Last Exam · with tools
52.3%
Science
GPQA Diamond
86.2%
Community preference (code)
Arena Elo (Code)
1527
Timeline
Release gapGPT-4.1 nano shipped 358 days before GLM-5.1

Which is better: GPT-4.1 nano or GLM-5.1?

GPT-4.1 nano and GLM-5.1 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. GPT-4.1 nano shipped 358 days before GLM-5.1, so benchmark comparisons should account for the intervening progress.

Context windows are 1M (GPT-4.1 nano) vs 200k (GLM-5.1). GPT-4.1 nano is proprietary, while GLM-5.1 is open weight.

Direct benchmark comparisons are unavailable — GPT-4.1 nano and GLM-5.1 don't publish scores on any of the same benchmarks.

Frequently asked questions

GPT-4.1 nano was released by OpenAI on Apr 14 2025.

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

GPT-4.1 nano has a 1M context window; GLM-5.1 has 200k.

GPT-4.1 nano is a proprietary model released by OpenAI. GLM-5.1 is an open weight model released by Z.ai.

Other comparisons