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

GPT-5.4 mini vs GPT-5.5-Pro

OpenAI
GPT-5.4 mini
OpenAI
GPT-5.5-Pro
Overview
CompanyOpenAIOpenAI
Release dateMar 17 2026Apr 23 2026
AccessProprietaryProprietary
Specifications
Context window
400k
Benchmarks
Nonsense detection
BullshitBench v2
32%
36%Best
Next.js coding
Next.js Evals
83%
Web browsing
BrowseComp
90.1%
Multidisciplinary reasoning
Humanity's Last Exam · with tools
57.2%
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 gapGPT-5.4 mini shipped 37 days before GPT-5.5-Pro

Which is better: GPT-5.4 mini or GPT-5.5-Pro?

GPT-5.5-Pro leads GPT-5.4 mini on 1 of the 1 benchmark they both report (BullshitBench v2). GPT-5.4 mini shipped 37 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.

On BullshitBench v2, GPT-5.5-Pro leads at 36% vs GPT-5.4 mini at 32%.

Frequently asked questions

GPT-5.4 mini was released by OpenAI on Mar 17 2026.

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

Other comparisons