Migrate from Prettier

This guide covers migrating from Prettier to Oxfmt.

When to migrate from Prettier

Migrate to Oxfmt if you want to keep a Prettier-like workflow while getting faster formatting and built-in formatting features. Choose Vite+ instead if you want Oxfmt as part of a larger unified toolchain.

• Move to Oxfmt for dedicated formatting.
• Move to Vite+ for an integrated workflow.
• Stay on Prettier if exact plugin behavior is still required.

Quick start

For simple setups, migrate with a single command:

npm

$ npm add -D oxfmt@latest && npx oxfmt --migrate=prettier && npx oxfmt

pnpm

$ pnpm add -D oxfmt@latest && pnpm oxfmt --migrate=prettier && pnpm oxfmt

yarn

$ yarn add -D oxfmt@latest && yarn oxfmt --migrate=prettier && yarn oxfmt

bun

$ bun add -D oxfmt@latest && bunx oxfmt --migrate=prettier && bunx oxfmt

Migrate with Skills

The migrate-oxfmt skill provides an interactive, agent-guided migration. Install it into your coding agent:

npx skills add https://github.com/oxc-project/oxc --skill migrate-oxfmt

Once installed, run /migrate-oxfmt to perform the migration.

Before you migrate

Oxfmt is compatible with Prettier v3.9.9 for many configurations.

Key differences:

• Default printWidth is 100 (Prettier uses 80)
• Prettier plugins are not supported (though some popular plugins have been implemented natively)
• Some options are not supported (see config reference)

See Unsupported features for details, and the compatibility matrix for file type support.

Known divergences

Oxfmt may intentionally differ from Prettier's output where Prettier's behavior is clearly a bug or inconsistent across similar cases. Each case is documented with its reason:

• JavaScript / TypeScript
• CSS / SCSS / Less
• GraphQL
• YAML
• Markdown
• Embedded formatting

Step 1: Upgrade Prettier to v3.9.9 (optional)

Oxfmt's output is closest to Prettier v3.9.9. Upgrading first minimizes formatting differences.

Step 2: Install Oxfmt

npm

$ npm add -D oxfmt@latest

pnpm

$ pnpm add -D oxfmt@latest

yarn

$ yarn add -D oxfmt@latest

bun

$ bun add -D oxfmt@latest

deno

$ deno add -D npm:oxfmt@latest

Step 3: Migrate configuration

Oxfmt uses .oxfmtrc.json, .oxfmtrc.jsonc, oxfmt.config.ts, or oxfmt.config.mts. Basic example:

.oxfmtrc.jsonc

{
  "$schema": "./node_modules/oxfmt/configuration_schema.json",
  "printWidth": 80,
}

Run oxfmt --migrate prettier to convert your Prettier config automatically.

It reads the Prettier config in the current directory and creates .oxfmtrc.json:

• Supported config formats:
  • prettier field in package.json, including shareable configs
  • .prettierrc (JSON only), .prettierrc.json
  • JS/TS configs (.prettierrc.*, prettier.config.*)
• YAML, JSON5 and TOML configs are not supported. Convert them to JSON or JS first.
• Only Prettier-compatible options are migrated. Others are skipped with a warning.
• overrides are migrated, and overrides[].options.parser becomes associations.
• .prettierignore patterns are migrated to ignorePatterns.
• Options of prettier-plugin-tailwindcss, prettier-plugin-svelte, prettier-plugin-astro and prettier-plugin-packagejson are migrated to the built-in equivalents. Other plugins are skipped with a warning.
• printWidth is set to 80 if not specified, to keep Prettier's default.

Things to do manually:

• JS/TS configs are evaluated and migrated as static values. Port any logic (e.g. environment branches) to oxfmt.config.ts.
• Nested configs are not searched. Run oxfmt --migrate prettier in each directory that has a Prettier config.
• Review the warnings printed at the end.

prettierrc.js example

Before:

prettierrc.js

module.exports = {
  singleQuote: true,
  jsxSingleQuote: true,
};

After (oxfmt.config.ts):

oxfmt.config.ts

import { defineConfig } from "oxfmt";

export default defineConfig({
  singleQuote: true,
  jsxSingleQuote: true,
  printWidth: 80,
});

prettierrc.yaml example

Before:

prettierrc.yaml

trailingComma: "es5"
tabWidth: 4
semi: false
singleQuote: true

After (.oxfmtrc.jsonc):

.oxfmtrc.jsonc

{
  "$schema": "./node_modules/oxfmt/configuration_schema.json",
  "trailingComma": "es5",
  "tabWidth": 4,
  "semi": false,
  "singleQuote": true,
  "printWidth": 80,
}

Step 4: Update scripts

package.json scripts

{
  "scripts": {
-   "format": "prettier --write .",
+   "format": "oxfmt",
-   "format:check": "prettier --check ."
+   "format:check": "oxfmt --check"
  }
}

CI workflows

  - name: Check formatting
-   run: yarn prettier --check .
+   run: yarn oxfmt --check

Git hooks (husky, lint-staged)

In package.json:

"lint-staged": {
- "*": "prettier --write --no-error-on-unmatched-pattern"
+ "*": "oxfmt --no-error-on-unmatched-pattern"
}

Step 5: Run formatter

npm run format

Uninstall Prettier if it is no longer needed.

Optional steps

Update editor integrations

See Setup editors.

Update documentation

Update references to Prettier in CONTRIBUTING.md, AGENTS.md, and CLAUDE.md if applicable.

Update lint rules

Remove eslint-plugin-prettier if present. If needed, it can be replaced by a oxfmt --check job in your CI pipelines.

Note that if you intend to continue using ESLint, you should keep or add eslint-config-prettier to disable styling-related ESLint rules that might conflict with Oxfmt. eslint-config-prettier is different from eslint-plugin-prettier, as it has no new lint rules. It is only a config.

Also, consider migrating to Oxlint.

Update .git-blame-ignore-revs

Add the reformatting commit SHA to .git-blame-ignore-revs to hide it from git blame.

Replace .prettierignore with "ignorePatterns"

If you no longer use Prettier, you can optionally move its contents from .prettierignore to "ignorePatterns" in your Oxfmt config. oxfmt --migrate prettier already does this, so you can delete .prettierignore afterward. Note that .prettierignore applies globally, while ignorePatterns is scoped to the config file it belongs to. In a nested config setup, this may change which files are ignored. See Ignore files for more information.

Update // prettier-ignore comments

Oxfmt supports // prettier-ignore comments, but also supports // oxfmt-ignore comments.

However, // oxfmt-ignore will only work for JS and TS files. See Inline ignore comments for more information.