minimizer-webpack-plugin

This plugin minifies your assets in a webpack build. It ships with several built-in minimizers covering JavaScript, JSON, HTML, and CSS — pick one with the minify option and target the right files with test.

JavaScript minimizers:

terser — MinimizerPlugin.terserMinify (default). The same JavaScript-based minifier that webpack uses out of the box; produces small, well-tested output and supports the full set of extractComments modes.
uglify-js — MinimizerPlugin.uglifyJsMinify. ES5-only minifier, useful when you specifically need UglifyJS-compatible output. Requires npm install --save-dev uglify-js.
@swc/core — MinimizerPlugin.swcMinify. A very fast Rust-based JavaScript/TypeScript minifier. Requires npm install --save-dev @swc/core.
esbuild — MinimizerPlugin.esbuildMinify. An extremely fast JS bundler/minifier; legal comments are always preserved (no extractComments support). Requires npm install --save-dev esbuild.

JSON minimizer:

JSON.stringify — MinimizerPlugin.jsonMinify. Built in (no extra dependency); supports space and replacer options.

HTML minimizers:

html-minifier-terser — MinimizerPlugin.htmlMinifierTerser. The default HTML minimizer. JavaScript-based, no native dependency. Requires npm install --save-dev html-minifier-terser.
@swc/html — MinimizerPlugin.swcMinifyHtml (full HTML documents) and MinimizerPlugin.swcMinifyHtmlFragment (HTML fragments, e.g. <template> content). Very fast Rust-based platform for the Web. Requires npm install --save-dev @swc/html.
@minify-html/node — MinimizerPlugin.minifyHtmlNode. A Rust HTML minifier optimised for speed and effectiveness. Requires npm install --save-dev @minify-html/node.

CSS minimizers:

cssnano — MinimizerPlugin.cssnanoMinify. The default CSS minimizer. Built on top of PostCSS. Requires npm install --save-dev cssnano postcss.
csso — MinimizerPlugin.cssoMinify. A CSS minifier with structural optimisations. Requires npm install --save-dev csso.
clean-css — MinimizerPlugin.cleanCssMinify. A widely-used CSS optimiser. Requires npm install --save-dev clean-css.
esbuild — MinimizerPlugin.esbuildMinifyCss. Very fast CSS minification using esbuild's CSS loader. Requires npm install --save-dev esbuild.
lightningcss — MinimizerPlugin.lightningCssMinify. A Rust-based CSS parser, transformer, and minifier. Requires npm install --save-dev lightningcss.
@swc/css — MinimizerPlugin.swcMinifyCss. A very fast Rust-based CSS minifier. Requires npm install --save-dev @swc/css.

All of the non-default minimizers are declared as optional peer dependencies — install only the ones you actually use. You can also stack multiple MinimizerPlugin instances in the same build to handle different file types with different minimizers (see Examples).

Getting Started

Webpack v5 comes with the latest minimizer-webpack-plugin out of the box. If you are using Webpack v5 or above and wish to customize the options, you will still need to install minimizer-webpack-plugin. Using Webpack v4, you have to install terser-webpack-plugin v4 (minimizer-webpack-plugin is only published for Webpack v5+).

To begin, you'll need to install minimizer-webpack-plugin:

npm install minimizer-webpack-plugin --save-dev

or

yarn add -D minimizer-webpack-plugin

or

pnpm add -D minimizer-webpack-plugin

Then add the plugin to your webpack configuration. For example:

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [new MinimizerPlugin()],
  },
};

Finally, run webpack using the method you normally use (e.g., via CLI or an npm script).

Note about source maps

Works only with source-map, inline-source-map, hidden-source-map and nosources-source-map values for the devtool option.

Why?

eval wraps modules in eval("string") and the minimizer does not handle strings.
cheap has no column information and the minimizer generates only a single line, which leaves only a single mapping.

Using supported devtool values enable source map generation.

Options

test
include
exclude
parallel
minify
minimizerOptions
extractComments

`test`

Type:

type test = string | RegExp | (string | RegExp)[];

Default: /\.m?js(\?.*)?$/i

Test to match files against.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        test: /\.js(\?.*)?$/i,
      }),
    ],
  },
};

`include`

Type:

type include = string | RegExp | (string | RegExp)[];

Default: undefined

Files to include.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        include: /\/includes/,
      }),
    ],
  },
};

`exclude`

Type:

type exclude = string | RegExp | (string | RegExp)[];

Default: undefined

Files to exclude.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        exclude: /\/excludes/,
      }),
    ],
  },
};

`parallel`

Type:

type parallel = boolean | number;

Default: true

Use multi-process parallel running to improve the build speed.

Default number of concurrent runs: os.cpus().length - 1 or os.availableParallelism() - 1 (if this function is supported).

Note

Parallelization can speedup your build significantly and is therefore highly recommended.

Warning

If you use Circle CI or any other environment that doesn't provide the real available count of CPUs then you need to explicitly set up the number of CPUs to avoid Error: Call retries were exceeded (see #143, #202).

`boolean`

Enable/disable multi-process parallel running.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        parallel: true,
      }),
    ],
  },
};

`number`

Enable multi-process parallel running and set number of concurrent runs.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        parallel: 4,
      }),
    ],
  },
};

`minify`

Type:

type minifyFn = (
  input: Record<string, string>,
  sourceMap: import("@jridgewell/trace-mapping").SourceMapInput | undefined,
  minifyOptions: {
    module?: boolean | undefined;
    ecma?: import("terser").ECMA | undefined;
  },
  extractComments:
    | boolean
    | "all"
    | "some"
    | RegExp
    | ((
        astNode: any,
        comment: {
          value: string;
          type: "comment1" | "comment2" | "comment3" | "comment4";
          pos: number;
          line: number;
          col: number;
        },
      ) => boolean)
    | {
        condition?:
          | boolean
          | "all"
          | "some"
          | RegExp
          | ((
              astNode: any,
              comment: {
                value: string;
                type: "comment1" | "comment2" | "comment3" | "comment4";
                pos: number;
                line: number;
                col: number;
              },
            ) => boolean)
          | undefined;
        filename?: string | ((fileData: any) => string) | undefined;
        banner?:
          | string
          | boolean
          | ((commentsFile: string) => string)
          | undefined;
      }
    | undefined,
) => Promise<{
  code: string;
  map?: import("@jridgewell/trace-mapping").SourceMapInput | undefined;
  errors?: (string | Error)[] | undefined;
  warnings?: (string | Error)[] | undefined;
  extractedComments?: string[] | undefined;
}>;

type minify = minifyFn | minifyFn[];

Default: MinimizerPlugin.terserMinify

Allows you to override the default minify function. By default plugin uses terser package. Useful for using and testing unpublished versions or forks.

An array of functions can also be provided. Each minimizer can expose a filter(name, info) helper that decides whether it should run on a given asset; the plugin dispatches each asset only to the minimizers whose filter accepts it (or runs them all when no filter is set). All built-in minimizers ship with a filter that matches their natural extension, so a single plugin instance and a single worker pool can handle JS, CSS, HTML and JSON together without juggling multiple MinimizerPlugin instances — just widen test to let those asset types reach the dispatcher:

new MinimizerPlugin({
  test: /\.(?:[cm]?js|css|html?|json)(\?.*)?$/i,
  minify: [
    MinimizerPlugin.terserMinify,
    MinimizerPlugin.cssnanoMinify,
    MinimizerPlugin.htmlMinifierTerser,
    MinimizerPlugin.jsonMinify,
  ],
});

When more than one minimizer in the array claims the same asset, the chain semantic still applies: the output of each accepting minimizer is fed as input to the next. The minimizerOptions option may be an array (index-paired with minify) or a single object reused by every minimizer.

The test option always defaults to /\.[cm]?js(\?.*)?$/i. When you mix asset types in a single plugin instance, widen test so non-JS assets reach the dispatcher (for example test: /\.(?:[cm]?js|css|html?|json)(\?.*)?$/i).

Warning

Always use require inside minify function when parallel option enabled.

`function`

webpack.config.js

// Can be async
const minify = (input, sourceMap, minimizerOptions, extractsComments) => {
  // The `minimizerOptions` argument contains options from the `minimizerOptions` plugin option
  // You can use `minimizerOptions.myCustomOption`

  // Custom logic for extract comments
  const { map, code } = require("uglify-module") // Or require('./path/to/uglify-module')
    .minify(input, {
      /* Your options for minification */
    });

  return { map, code, warnings: [], errors: [], extractedComments: [] };
};

// Used to regenerate `fullhash`/`chunkhash` between different implementation
// Example: you fix a bug in custom minimizer/custom function, but unfortunately webpack doesn't know about it, so you will get the same fullhash/chunkhash
// to avoid this you can provide version of your custom minimizer
// You don't need if you use only `contenthash`
minify.getMinimizerVersion = () => {
  let packageJson;

  try {
    packageJson = require("uglify-module/package.json");
  } catch (error) {
    // Ignore
  }

  return packageJson && packageJson.version;
};

// Restrict the minimizer to the assets it can actually handle. The plugin
// skips assets for which `filter` returns `false` and (when an array of
// minimizers is used) dispatches each asset only to the minimizers that
// accept it. Returning `undefined` is treated as accept.
minify.filter = (name) => /\.[cm]?js(\?.*)?$/i.test(name);

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minimizerOptions: {
          myCustomOption: true,
        },
        minify,
      }),
    ],
  },
};

`array`

If an array of functions is passed to the minify option, each asset is dispatched to the minimizers whose filter accepts it. When more than one minimizer accepts the same asset the output of each is fed as input to the next one (the chain semantic). The minimizerOptions option can be either an array of option objects (index-paired with minify) or a single object that will be shared by all minimizers. Warnings, errors and extracted comments from all running minimizers are merged together.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minify: [MinimizerPlugin.terserMinify, MinimizerPlugin.swcMinify],
        // `minimizerOptions` can be an array of options, one per `minify` entry
        minimizerOptions: [
          // Options for `MinimizerPlugin.terserMinify`
          { mangle: false },
          // Options for `MinimizerPlugin.swcMinify`
          {},
        ],
      }),
    ],
  },
};

A single plugin instance can also handle multiple asset types — the built-in minimizers each ship with a filter matching their natural extension, so JS, CSS, HTML and JSON can all be minified by one shared worker pool:

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        // `test` still defaults to JS only, so widen it to catch every
        // asset type you want the dispatcher to consider.
        test: /\.(?:[cm]?js|css|html?|json)(\?.*)?$/i,
        minify: [
          MinimizerPlugin.terserMinify,
          MinimizerPlugin.cssnanoMinify,
          MinimizerPlugin.htmlMinifierTerser,
          MinimizerPlugin.jsonMinify,
        ],
      }),
    ],
  },
};

`minimizerOptions`

Type:

interface minimizerOptions {
  compress?: boolean | CompressOptions;
  ecma?: ECMA;
  enclose?: boolean | string;
  ie8?: boolean;
  keep_classnames?: boolean | RegExp;
  keep_fnames?: boolean | RegExp;
  mangle?: boolean | MangleOptions;
  module?: boolean;
  nameCache?: object;
  format?: FormatOptions;
  /** @deprecated */
  output?: FormatOptions;
  parse?: ParseOptions;
  safari10?: boolean;
  sourceMap?: boolean | SourceMapOptions;
  toplevel?: boolean;
}

type options = minimizerOptions | minimizerOptions[];

Default: default

Options for the active minimizer. With the default Terser minify, see Terser's minify options.

When the minify option is an array of minimizers, minimizerOptions can also be an array. Each element is passed to the minimizer at the same index in the minify array. If a single object is provided instead, it is reused for every minimizer.

Note

terserOptions is kept as a deprecated alias of minimizerOptions for backwards compatibility — passing either is equivalent. If both are set, minimizerOptions wins. Prefer minimizerOptions in new code.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minimizerOptions: {
          ecma: undefined,
          parse: {},
          compress: {},
          mangle: true, // Note `mangle.properties` is `false` by default.
          module: false,
          // Deprecated
          output: null,
          format: null,
          toplevel: false,
          nameCache: null,
          ie8: false,
          keep_classnames: undefined,
          keep_fnames: false,
          safari10: false,
        },
      }),
    ],
  },
};

`extractComments`

Type:

type extractComments =
  | boolean
  | string
  | RegExp
  | ((
      astNode: any,
      comment: {
        value: string;
        type: "comment1" | "comment2" | "comment3" | "comment4";
        pos: number;
        line: number;
        col: number;
      },
    ) => boolean)
  | {
      condition?:
        | boolean
        | "all"
        | "some"
        | RegExp
        | ((
            astNode: any,
            comment: {
              value: string;
              type: "comment1" | "comment2" | "comment3" | "comment4";
              pos: number;
              line: number;
              col: number;
            },
          ) => boolean)
        | undefined;
      filename?: string | ((fileData: any) => string) | undefined;
      banner?:
        | string
        | boolean
        | ((commentsFile: string) => string)
        | undefined;
    };

Default: true

Whether comments shall be extracted to a separate file, (see details).

By default, extract only comments using /^\**!|@preserve|@license|@cc_on/i RegExp condition and remove remaining comments.

If the original file is named foo.js, then the comments will be stored to foo.js.LICENSE.txt.

The minimizerOptions.format.comments option specifies whether the comment will be preserved - i.e., it is possible to preserve some comments (e.g. annotations) while extracting others, or even preserve comments that have already been extracted.

`boolean`

Enable/disable extracting comments.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        extractComments: true,
      }),
    ],
  },
};

`string`

Extract all or some (use the /^\**!|@preserve|@license|@cc_on/i RegExp) comments.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        extractComments: "all",
      }),
    ],
  },
};

`RegExp`

All comments that match the given expression will be extracted to a separate file.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        extractComments: /@extract/i,
      }),
    ],
  },
};

`function`

All comments that match the given expression will be extracted to a separate file.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        extractComments: (astNode, comment) => {
          if (/@extract/i.test(comment.value)) {
            return true;
          }

          return false;
        },
      }),
    ],
  },
};

`object`

Allows you to customize condition for extracting comments, and specify the extracted file name and banner.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        extractComments: {
          condition: /^\**!|@preserve|@license|@cc_on/i,
          filename: (fileData) =>
            // The "fileData" argument contains object with "filename", "basename", "query" and "hash"
            `${fileData.filename}.LICENSE.txt${fileData.query}`,
          banner: (licenseFile) =>
            `License information can be found in ${licenseFile}`,
        },
      }),
    ],
  },
};

`condition`

Type:

type condition =
  | boolean
  | "all"
  | "some"
  | RegExp
  | ((
      astNode: any,
      comment: {
        value: string;
        type: "comment1" | "comment2" | "comment3" | "comment4";
        pos: number;
        line: number;
        col: number;
      },
    ) => boolean)
  | undefined;

The condition that determines which comments should be extracted.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        extractComments: {
          condition: "some",
          filename: (fileData) =>
            // The "fileData" argument contains object with "filename", "basename", "query" and "hash"
            `${fileData.filename}.LICENSE.txt${fileData.query}`,
          banner: (licenseFile) =>
            `License information can be found in ${licenseFile}`,
        },
      }),
    ],
  },
};

`filename`

Type:

type filename = string | ((fileData: any) => string) | undefined;

Default: [file].LICENSE.txt[query]

Available placeholders: [file], [query] and [filebase] ([base] for webpack 5).

The file where the extracted comments will be stored.

Default is to append the suffix .LICENSE.txt to the original filename.

Warning

We highly recommend using the .txt extension. Using .js/.cjs/.mjs extensions may conflict with existing assets, which leads to broken code.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        extractComments: {
          condition: /^\**!|@preserve|@license|@cc_on/i,
          filename: "extracted-comments.js",
          banner: (licenseFile) =>
            `License information can be found in ${licenseFile}`,
        },
      }),
    ],
  },
};

`banner`

Type:

type banner = string | boolean | ((commentsFile: string) => string) | undefined;

Default: /*! For license information please see ${commentsFile} */

The banner text that points to the extracted file and will be added at the top of the original file.

It can be false (no banner), a String, or a function<(string) -> String> that will be called with the filename where the extracted comments have been stored.

The banner will be wrapped in a comment.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        extractComments: {
          condition: true,
          filename: (fileData) =>
            // The "fileData" argument contains object with "filename", "basename", "query" and "hash"
            `${fileData.filename}.LICENSE.txt${fileData.query}`,
          banner: (commentsFile) =>
            `My custom banner about license information ${commentsFile}`,
        },
      }),
    ],
  },
};

Examples

Preserve Comments

Extract all legal comments (i.e. /^\**!|@preserve|@license|@cc_on/i) and preserve /@license/i comments.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minimizerOptions: {
          format: {
            comments: /@license/i,
          },
        },
        extractComments: true,
      }),
    ],
  },
};

Remove Comments

If you want to build without comments, use this config:

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minimizerOptions: {
          format: {
            comments: false,
          },
        },
        extractComments: false,
      }),
    ],
  },
};

`uglify-js`

UglifyJS is a JavaScript parser, minifier, compressor and beautifier toolkit.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minify: MinimizerPlugin.uglifyJsMinify,
        // `minimizerOptions` will be passed to `uglify-js`
        // Link to options - https://github.com/mishoo/UglifyJS#minify-options
        minimizerOptions: {},
      }),
    ],
  },
};

`swc`

swc is a super-fast compiler written in Rust, producing widely supported JavaScript from modern standards and TypeScript.

Warning

extractComments is supported with @swc/core >= 1.15.30. Only serializable extract conditions are supported: booleans, "some", "all", string patterns, RegExp values without flags, or object conditions that resolve to those forms. Function conditions and flagged regular expressions are not supported.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minify: MinimizerPlugin.swcMinify,
        // `minimizerOptions` will be passed to `swc` (`@swc/core`)
        // Link to options - https://swc.rs/docs/config-js-minify
        minimizerOptions: {},
      }),
    ],
  },
};

`esbuild`

esbuild is an extremely fast JavaScript bundler and minifier.

Warning

The extractComments option is not supported, and all legal comments (i.e. copyright, licenses and etc) will be preserved.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minify: MinimizerPlugin.esbuildMinify,
        // `minimizerOptions` will be passed to `esbuild`
        // Link to options - https://esbuild.github.io/api/#minify
        // Note: the `minify` options is true by default (and override other `minify*` options), so if you want to disable the `minifyIdentifiers` option (or other `minify*` options) please use:
        // minimizerOptions: {
        //   minify: false,
        //   minifyWhitespace: true,
        //   minifyIdentifiers: false,
        //   minifySyntax: true,
        // },
        minimizerOptions: {},
      }),
    ],
  },
};

JSON

Uses JSON.stringify() to minify your JSON files during the build process.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      // Keeps original terser plugin to minify JS files
      "...",
      // Will minify JSON files (they can come from copy-webpack-plugin or when you are using asset modules)
      new MinimizerPlugin({
        test: /\.json$/,
        minify: MinimizerPlugin.jsonMinify,
        // We are supporting `space` and `replacer` options, you can set them below
        minimizerOptions: {},
      }),
    ],
  },
};

HTML

The plugin can minify HTML assets too. Pick one of the bundled HTML minimizers and set test to match your HTML files.

Available HTML minimizers:

MinimizerPlugin.htmlMinifierTerser — uses html-minifier-terser.
MinimizerPlugin.swcMinifyHtml — uses @swc/html for full HTML documents (with doctype and <html>/<head>/<body> tags).
MinimizerPlugin.swcMinifyHtmlFragment — uses @swc/html for HTML fragments (e.g. content inside <template></template> or partial HTML strings).
MinimizerPlugin.minifyHtmlNode — uses @minify-html/node.

The HTML minimizers are optional peer dependencies — install only the one you actually use:

npm install --save-dev html-minifier-terser
# or
npm install --save-dev @swc/html
# or
npm install --save-dev @minify-html/node

Note

HTML assets typically come from plugins like copy-webpack-plugin, html-webpack-plugin, or webpack's asset modules.

Note

Whitespace handling differs between tools (defaults):

@swc/html — removes/collapses whitespace only in safe places (around html/body, inside <head>, between <meta>/<script>/<link> etc.).

html-minifier-terser — always collapses multiple whitespaces to a single space (never removes entirely); configurable via its options.

@minify-html/node — see its whitespace docs.

`html-minifier-terser`

html-minifier-terser is a JavaScript-based HTML minifier with no native dependency. It's the default HTML minimizer.

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      // Keeps the default Terser plugin for JS files
      "...",
      new MinimizerPlugin({
        test: /\.html(\?.*)?$/i,
        minify: MinimizerPlugin.htmlMinifierTerser,
        // Options - https://github.com/terser/html-minifier-terser#options-quick-reference
        minimizerOptions: {
          collapseWhitespace: true,
          removeComments: true,
        },
      }),
    ],
  },
};

`@swc/html` — HTML documents

Use swcMinifyHtml for complete HTML documents (i.e. with a doctype and <html>/<head>/<body> tags).

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      "...",
      new MinimizerPlugin({
        test: /\.html(\?.*)?$/i,
        minify: MinimizerPlugin.swcMinifyHtml,
        // Options - https://github.com/swc-project/bindings/blob/main/packages/html/index.ts
        minimizerOptions: {},
      }),
    ],
  },
};

`@swc/html` — HTML fragments

Use swcMinifyHtmlFragment for partial HTML — for example, content of <template></template> tags or HTML strings that get injected into another document.

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      "...",
      new MinimizerPlugin({
        test: /\.template\.html$/i,
        minify: MinimizerPlugin.swcMinifyHtmlFragment,
        // Options - https://github.com/swc-project/bindings/blob/main/packages/html/index.ts
        minimizerOptions: {},
      }),
    ],
  },
};

Note

The difference between swcMinifyHtml and swcMinifyHtmlFragment is the error reporting — invalid or broken syntax is reported at build time.

`@minify-html/node`

@minify-html/node is a Rust HTML minifier.

webpack.config.js

const Minimizer = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      "...",
      new Minimizer({
        test: /\.html(\?.*)?$/i,
        minify: Minimizer.minifyHtmlNode,
        // Options - https://github.com/wilsonzlin/minify-html#minification
        minimizerOptions: {},
      }),
    ],
  },
};

You can also stack multiple MinimizerPlugin instances to compress different files with different minify functions in the same build (e.g. JS with terserMinify, HTML with htmlMinifierTerser, JSON with jsonMinify).

CSS

The plugin can minify CSS assets too. Pick one of the bundled CSS minimizers and set test to match your CSS files.

Available CSS minimizers:

MinimizerPlugin.cssnanoMinify — uses cssnano (via postcss).
MinimizerPlugin.cssoMinify — uses csso.
MinimizerPlugin.cleanCssMinify — uses clean-css.
MinimizerPlugin.esbuildMinifyCss — uses esbuild with the CSS loader.
MinimizerPlugin.lightningCssMinify — uses lightningcss.
MinimizerPlugin.swcMinifyCss — uses @swc/css.

The CSS minimizers are optional peer dependencies — install only the ones you actually use:

npm install --save-dev cssnano postcss
# or
npm install --save-dev csso
# or
npm install --save-dev clean-css
# or
npm install --save-dev esbuild
# or
npm install --save-dev lightningcss
# or
npm install --save-dev @swc/css

Note

CSS assets typically come from plugins like mini-css-extract-plugin or webpack's asset modules.

`cssnano`

cssnano is the default CSS minimizer. It runs as a PostCSS plugin.

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      // Keeps the default Terser plugin for JS files
      "...",
      new MinimizerPlugin({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.cssnanoMinify,
        // Options - https://cssnano.github.io/cssnano/docs/config-file/
        minimizerOptions: {
          preset: "default",
        },
      }),
    ],
  },
};

`csso`

csso is a CSS minifier with structural optimisations.

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      "...",
      new MinimizerPlugin({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.cssoMinify,
        // Options - https://github.com/css/csso#minifysource-options
        minimizerOptions: {},
      }),
    ],
  },
};

`clean-css`

clean-css is a widely-used CSS optimiser.

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      "...",
      new MinimizerPlugin({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.cleanCssMinify,
        // Options - https://github.com/clean-css/clean-css#constructor-options
        minimizerOptions: {},
      }),
    ],
  },
};

`esbuild`

esbuild ships with a fast CSS minifier (used via its CSS loader).

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      "...",
      new MinimizerPlugin({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.esbuildMinifyCss,
        // Options - https://esbuild.github.io/api/#transform-api
        minimizerOptions: {},
      }),
    ],
  },
};

`lightningcss`

lightningcss is a Rust-based CSS parser, transformer, and minifier.

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      "...",
      new MinimizerPlugin({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.lightningCssMinify,
        // Options - https://lightningcss.dev/transpilation.html
        minimizerOptions: {},
      }),
    ],
  },
};

`@swc/css`

@swc/css is a Rust-based CSS minifier.

webpack.config.js

const MinimizerPlugin = require("minimizer-webpack-plugin");

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      "...",
      new MinimizerPlugin({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.swcMinifyCss,
        // Options - https://github.com/swc-project/bindings/blob/main/packages/css/index.ts
        minimizerOptions: {},
      }),
    ],
  },
};

Custom Minify Function

Override the default minify function - use uglify-js for minification.

webpack.config.js

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minify: (file, sourceMap) => {
          // https://github.com/mishoo/UglifyJS2#minify-options
          const uglifyJsOptions = {
            /* your `uglify-js` package options */
          };

          if (sourceMap) {
            uglifyJsOptions.sourceMap = {
              content: sourceMap,
            };
          }

          return require("uglify-js").minify(file, uglifyJsOptions);
        },
      }),
    ],
  },
};

Typescript

With default Terser minify function:

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin({
        minimizerOptions: {
          compress: true,
        },
      }),
    ],
  },
};

With built-in minify functions:

import { type JsMinifyOptions as SwcOptions } from "@swc/core";
import { type MinifyOptions as SwcCssOptions } from "@swc/css";
import {
  type FragmentOptions as SwcHtmlFragmentOptions,
  type Options as SwcHtmlOptions,
} from "@swc/html";
import { type OptionsOutput as CleanCssOptions } from "clean-css";
import { type Options as CssnanoOptions } from "cssnano";
import { type CompressOptions as CssoOptions } from "csso";
import { type TransformOptions as EsbuildOptions } from "esbuild";
import { type Options as HtmlMinifierTerserOptions } from "html-minifier-terser";
import { type TransformOptions as LightningCssOptions } from "lightningcss";
import { type MinifyOptions as TerserOptions } from "terser";
import { type MinifyOptions as UglifyJSOptions } from "uglify-js";

module.exports = {
  optimization: {
    minimize: true,
    minimizer: [
      new MinimizerPlugin<SwcOptions>({
        minify: MinimizerPlugin.swcMinify,
        minimizerOptions: {
          // `swc` options
        },
      }),
      new MinimizerPlugin<UglifyJSOptions>({
        minify: MinimizerPlugin.uglifyJsMinify,
        minimizerOptions: {
          // `uglif-js` options
        },
      }),
      new MinimizerPlugin<EsbuildOptions>({
        minify: MinimizerPlugin.esbuildMinify,
        minimizerOptions: {
          // `esbuild` options
        },
      }),

      // Alternative usage:
      new MinimizerPlugin<TerserOptions>({
        minify: MinimizerPlugin.terserMinify,
        minimizerOptions: {
          // `terser` options
        },
      }),

      // HTML minimizers
      new MinimizerPlugin<HtmlMinifierTerserOptions>({
        test: /\.html(\?.*)?$/i,
        minify: MinimizerPlugin.htmlMinifierTerser,
        minimizerOptions: {
          // `html-minifier-terser` options
        },
      }),
      new MinimizerPlugin<SwcHtmlOptions>({
        test: /\.html(\?.*)?$/i,
        minify: MinimizerPlugin.swcMinifyHtml,
        minimizerOptions: {
          // `@swc/html` options
        },
      }),
      new MinimizerPlugin<SwcHtmlFragmentOptions>({
        test: /\.template\.html$/i,
        minify: MinimizerPlugin.swcMinifyHtmlFragment,
        minimizerOptions: {
          // `@swc/html` fragment options
        },
      }),

      // CSS minimizers
      new MinimizerPlugin<CssnanoOptions>({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.cssnanoMinify,
        minimizerOptions: {
          // `cssnano` options
        },
      }),
      new MinimizerPlugin<CssoOptions>({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.cssoMinify,
        minimizerOptions: {
          // `csso` options
        },
      }),
      new MinimizerPlugin<CleanCssOptions>({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.cleanCssMinify,
        minimizerOptions: {
          // `clean-css` options
        },
      }),
      new MinimizerPlugin<EsbuildOptions>({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.esbuildMinifyCss,
        minimizerOptions: {
          // `esbuild` options (CSS loader)
        },
      }),
      new MinimizerPlugin<LightningCssOptions>({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.lightningCssMinify,
        minimizerOptions: {
          // `lightningcss` options
        },
      }),
      new MinimizerPlugin<SwcCssOptions>({
        test: /\.css(\?.*)?$/i,
        minify: MinimizerPlugin.swcMinifyCss,
        minimizerOptions: {
          // `@swc/css` options
        },
      }),
    ],
  },
};

Contributing

We welcome all contributions! If you're new here, please take a moment to review our contributing guidelines before submitting issues or pull requests.

CONTRIBUTING

License

MIT

Name		Name	Last commit message	Last commit date
Latest commit History 422 Commits
.changeset		.changeset
.github/workflows		.github/workflows
.husky		.husky
scripts		scripts
src		src
test		test
types		types
.cspell.json		.cspell.json
.editorconfig		.editorconfig
.gitattributes		.gitattributes
.gitignore		.gitignore
.prettierignore		.prettierignore
CHANGELOG.md		CHANGELOG.md
LICENSE		LICENSE
README.md		README.md
babel.config.js		babel.config.js
eslint.config.mjs		eslint.config.mjs
jest.config.js		jest.config.js
lint-staged.config.js		lint-staged.config.js
package-lock.json		package-lock.json
package.json		package.json
tsconfig.json		tsconfig.json

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minimizer-webpack-plugin

Getting Started

Note about source maps

Options

test

include

exclude

parallel

boolean

number

minify

function

array

minimizerOptions

extractComments

boolean

string

RegExp

function

object

condition

filename

banner

Examples

Preserve Comments

Remove Comments

uglify-js

swc

esbuild

JSON

HTML

html-minifier-terser

@swc/html — HTML documents

@swc/html — HTML fragments

@minify-html/node

CSS

cssnano

csso

clean-css

esbuild

lightningcss

@swc/css

Custom Minify Function

Typescript

Contributing

License

About

Topics

Resources

License

Code of conduct

Contributing

Security policy

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Releases 88

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Languages

`test`

`include`

`exclude`

`parallel`

`boolean`

`number`

`minify`

`function`

`array`

`minimizerOptions`

`extractComments`

`boolean`

`string`

`RegExp`

`function`

`object`

`condition`

`filename`

`banner`

`uglify-js`

`swc`

`esbuild`

`html-minifier-terser`

`@swc/html` — HTML documents

`@swc/html` — HTML fragments

`@minify-html/node`

`cssnano`

`csso`

`clean-css`

`esbuild`

`lightningcss`

`@swc/css`

Packages