This plugin enables more fine grained control of source map generation. It is also enabled automatically by certain settings of the devtool configuration option.

new webpack.SourceMapDevToolPlugin(options);


The following options are supported:

  • test (string RegExp [string, RegExp]): Include source maps for modules based on their extension (defaults to .js, .mjs, and .css).

  • include (string RegExp [string, RegExp]): Include source maps for module paths that match the given value.

  • exclude (string RegExp [string, RegExp]): Exclude modules that match the given value from source map generation.

  • filename (string): Defines the output filename of the SourceMap (will be inlined if no value is provided).

  • append (string function): Appends the given value to the original asset. Usually the #sourceMappingURL comment. [url] is replaced with a URL to the source map file. Since webpack v4.36.0, path parameters are supported: [chunk], [filename] and [contenthash]. Setting append to false disables the appending.

    Starting from version 5.84.0, webpack allows the append option to be a function that accepts path data and an asset info object as arguments, and returns a string.

    (pathData: PathData, assetInfo?: AssetInfo) => string;
  • moduleFilenameTemplate (string): See output.devtoolModuleFilenameTemplate.

  • fallbackModuleFilenameTemplate (string): See link above.

  • namespace (string): See output.devtoolNamespace.

  • module = true (boolean): Indicates whether loaders should generate source maps.

  • columns = true (boolean): Indicates whether column mappings should be used.

  • noSources = false (boolean): Prevents the source file content from being included in the source map.

  • publicPath (string): Emits absolute URLs with public path prefix, e.g.

  • fileContext (string): Makes the [file] argument relative to this directory.

  • sourceRoot (string): Provide a custom value for the sourceRoot property in the SourceMap.

The fileContext option is useful when you want to store source maps in an upper level directory to avoid ../../ appearing in the absolute [url].


The following examples demonstrate some common use cases for this plugin.

Basic Use Case

You can use the following code to replace the configuration option devtool: inline-source-map with an equivalent custom plugin configuration:

module.exports = {
  // ...
  devtool: false,
  plugins: [new webpack.SourceMapDevToolPlugin({})],

Exclude Vendor Maps

The following code would exclude source maps for any modules in the vendor.js bundle:

new webpack.SourceMapDevToolPlugin({
  filename: '[file].map[query]',
  exclude: ['vendor.js'],

Host Source Maps Externally

Set a URL for source maps. Useful for hosting them on a host that requires authorization.

new webpack.SourceMapDevToolPlugin({
  append: '\n//# sourceMappingURL=[url]',
  filename: '[file].map[query]',

And for cases when source maps are stored in the upper level directory:

|- dist
  |- public
    |- bundle-[hash].js
  |- sourcemaps
    |- bundle-[hash]

With the following config:

new webpack.SourceMapDevToolPlugin({
  filename: 'sourcemaps/[file].map',
  publicPath: '',
  fileContext: 'public',

Will produce the following URL:[hash]

Further Reading

6 Contributors