클래스 정렬과 Prettier 플러그인

When multiple Tailwind developers work on the same project, utility classes inevitably appear in different orders in different files. While class order rarely affects rendering, inconsistent ordering makes code reviews noisy and diff outputs hard to read. A consistent canonical order helps everyone understand component structure at a glance.

prettier-plugin-tailwindcss is the official Tailwind CSS Prettier plugin maintained by the Tailwind team. It automatically sorts utility classes in your markup into a canonical order every time Prettier formats a file. No manual effort is needed — just save and the classes reorganize themselves.

After installation, add the plugin to your Prettier configuration file. The plugin works automatically with no extra options required for most projects. If your tailwind.config.js is in a non-standard location, point Prettier to it with the tailwindConfig option.

The plugin sorts classes following Tailwind's recommended order: layout utilities first (display, position, overflow), then box model (width, height, padding, margin), then typography, then visual properties (background, border, shadow), and finally interactive states and responsive variants. This reflects how CSS specificity cascades.

Once configured, run Prettier across all your template files to apply sorting in bulk. Add a format script to your package.json for easy access. Developers should run this before every commit, or better yet, wire it into a pre-commit hook with Husky.

For the best developer experience, configure your editor to format on save. In VS Code, install the Prettier extension and set editor.formatOnSave: true in your settings. This means classes sort automatically whenever you save a file, keeping your markup tidy without any extra steps.

Automating formatting at commit time with Husky and lint-staged ensures no unsorted classes ever enter the repository. When a developer commits, only the staged files are formatted and re-staged — a fast, focused operation even in large projects.

The plugin handles JSX and TSX files too, sorting classes inside className attributes and string arguments to utilities like clsx and tailwind-merge. It uses static analysis to find class strings, so dynamically constructed strings are left unchanged — only static string literals are sorted.

The plugin recognizes class strings passed to popular helpers like clsx, cn, and tailwind-merge when called with string arguments. This means your conditional class logic stays sorted even when spread across multiple arguments, keeping composition patterns clean and readable.

Add Prettier's --check mode to your CI pipeline to fail builds when files contain unsorted classes. This ensures that even if a developer skips the pre-commit hook, unsorted code never merges into main. The check exits with a non-zero status code when formatting differences are found.

The plugin sorts known Tailwind classes but leaves unrecognized class names in place at the end. If you use custom utilities added via plugins, configure the tailwindConfig option so the plugin is aware of them. Custom classes that the plugin cannot identify will still appear but will not break the sort of recognized utilities.

In this lesson you learned: installing and configuring prettier-plugin-tailwindcss to automate class sorting, integrating with editor format-on-save for a seamless workflow, and enforcing sorted classes in CI with Prettier's check mode. Next up we explore linting Tailwind with ESLint.