url-loader

A loader for webpack which transforms files into base64 URIs.

Getting Started

To begin, you'll need to install url-loader:

$ npm install url-loader --save-dev

url-loader works like file-loader, but can return a DataURL if the file is smaller than a byte limit.

index.js

import img from './image.png';

webpack.config.js

module.exports = {
  module: {
    rules: [
      {
        test: /\.(png|jpg|gif)$/i,
        use: [
          {
            loader: 'url-loader',
            options: {
              limit: 8192,
            },
          },
        ],
      },
    ],
  },
};

And run webpack via your preferred method.

Options

`fallback`

Type: String Default: 'file-loader'

Specifies an alternative loader to use when a target file's size exceeds the limit set in the limit option.

webpack.config.js

module.exports = {
  module: {
    rules: [
      {
        test: /\.(png|jpg|gif)$/i,
        use: [
          {
            loader: 'url-loader',
            options: {
              fallback: require.resolve('responsive-loader'),
            },
          },
        ],
      },
    ],
  },
};

The fallback loader will receive the same configuration options as url-loader.

For example, to set the quality option of a responsive-loader above use:

webpack.config.js

module.exports = {
  module: {
    rules: [
      {
        test: /\.(png|jpg|gif)$/i,
        use: [
          {
            loader: 'url-loader',
            options: {
              fallback: require.resolve('responsive-loader'),
              quality: 85,
            },
          },
        ],
      },
    ],
  },
};

`limit`

Type: Number|Boolean|String Default: undefined

The limit can be specified via loader options and defaults to no limit.

`Number|String`

A Number or String specifying the maximum size of a file in bytes. If the file size is equal or greater than the limit file-loader will be used (by default) and all query parameters are passed to it. Using an alternative to file-loader is enabled via the fallback option.

webpack.config.js

module.exports = {
  module: {
    rules: [
      {
        test: /\.(png|jpg|gif)$/i,
        use: [
          {
            loader: 'url-loader',
            options: {
              limit: 8192,
            },
          },
        ],
      },
    ],
  },
};

`Boolean`

Enable or disable transform files into base64.

webpack.config.js

module.exports = {
  module: {
    rules: [
      {
        test: /\.(png|jpg|gif)$/i,
        use: [
          {
            loader: 'url-loader',
            options: {
              limit: false,
            },
          },
        ],
      },
    ],
  },
};

`mimetype`

Type: String Default: (file extension)

Sets the MIME type for the file to be transformed. If unspecified the file extensions will be used to lookup the MIME type.

webpack.config.js

module.exports = {
  module: {
    rules: [
      {
        test: /\.(png|jpg|gif)$/i,
        use: [
          {
            loader: 'url-loader',
            options: {
              mimetype: 'image/png',
            },
          },
        ],
      },
    ],
  },
};

`esModule`

Type: Boolean Default: true

By default, file-loader generates JS modules that use the ES modules syntax. There are some cases in which using ES modules is beneficial, like in the case of module concatenation and tree shaking.

You can enable a CommonJS module syntax using:

webpack.config.js

module.exports = {
  module: {
    rules: [
      {
        test: /\.css$/,
        use: [
          {
            loader: 'url-loader',
            options: {
              esModule: false,
            },
          },
        ],
      },
    ],
  },
};