Tailwind CSS v4.2 — LLM Reference Guide

Current Version: 4.2.1 (February 2026) Tailwind CSS v4 is a ground-up rewrite. If your prior knowledge is based on v3, read the entire "Migration Pitfalls" section before generating any code.

1. Installation

Vite (Recommended — fastest)

# npm
npm i tailwindcss @tailwindcss/vite

# pnpm
pnpm add tailwindcss @tailwindcss/vite