Visualize size of webpack output files with an interactive zoomable treemap.
The file-upload-example app in all its unoptimized glory looks like this in the bundle-analyzer: webpack-bundle-analyzer webpack-build-log.json dist/app. And will result in a diagram similar to this: Our (intentionally unoptimized) app has a whopping 1.69MB stat size. The app size is 1.76MB parsed and 399.17KB gzipped. We're always striving towards keeping our website's JavaScript as small as possible. If you're using webpack(er), you can use the webpack-bundle-analyzer plugin to get a good overview, which of your JavaScript modules take up how much space, and where you can optimize. // Uncomment this code to show.
Install
Usage (as a plugin)
It will create an interactive treemap visualization of the contents of all your bundles.
This module will help you:
- Realize what's really inside your bundle
- Find out what modules make up the most of its size
- Find modules that got there by mistake
- Optimize it!
And the best thing is it supports minified bundles! It parses them to get real size of bundled modules.And it also shows their gzipped sizes!
Options (for plugin)
Name | Type | Description |
---|---|---|
analyzerMode | One of: server , static , disabled | Default: server . In server mode analyzer will start HTTP server to show bundle report. In static mode single HTML file with bundle report will be generated. In disabled mode you can use this plugin to just generate Webpack Stats JSON file by setting generateStatsFile to true . |
analyzerHost | {String} | Default: 127.0.0.1 . Host that will be used in server mode to start HTTP server. |
analyzerPort | {Number} | Default: 8888 . Port that will be used in server mode to start HTTP server. |
reportFilename | {String} | Default: report.html . Path to bundle report file that will be generated in static mode. It can be either an absolute path or a path relative to a bundle output directory (which is output.path in webpack config). |
defaultSizes | One of: stat , parsed , gzip | Default: parsed . Module sizes to show in report by default. Size definitions section describes what these values mean. |
openAnalyzer | {Boolean} | Default: true . Automatically open report in default browser. |
generateStatsFile | {Boolean} | Default: false . If true , webpack stats JSON file will be generated in bundle output directory |
statsFilename | {String} | Default: stats.json . Name of webpack stats JSON file that will be generated if generateStatsFile is true . It can be either an absolute path or a path relative to a bundle output directory (which is output.path in webpack config). |
statsOptions | null or {Object} | Default: null . Options for stats.toJson() method. For example you can exclude sources of your modules from stats file with source: false option. See more options here. |
excludeAssets | {null|pattern|pattern[]} where pattern equals to {String|RegExp|function} | Default: null . Patterns that will be used to match against asset names to exclude them from the report. If pattern is a string it will be converted to RegExp via new RegExp(str) . If pattern is a function it should have the following signature (assetName: string) => boolean and should return true to exclude matching asset. If multiple patterns are provided asset should match at least one of them to be excluded. |
logLevel | One of: info , warn , error , silent | Default: info . Used to control how much details the plugin outputs. |
Usage (as a CLI utility)
You can analyze an existing bundle if you have a webpack stats JSON file.
You can generate it using
BundleAnalyzerPlugin
with generateStatsFile
option set to true
or with this simplecommand:If you're on Windows and using PowerShell, you can generate the stats file with this command to avoid BOM issues:
Then you can run the CLI tool.
Options (for CLI)
Arguments are documented below:
bundleStatsFile
Path to webpack stats JSON file
bundleDir
Directory containing all generated bundles.
options
Size definitions
webpack-bundle-analyzer reports three values for sizes.
defaultSizes
can be used to control which of these is shown by default. The different reported sizes are:stat
This is the 'input' size of your files, before any transformations likeminification.
It is called 'stat size' because it's obtained from Webpack'sstats object.
parsed
This is the 'output' size of your files. If you're using a Webpack plugin suchas Uglify, then this value will reflect the minified size of your code.
gzip
This is the size of running the parsed bundles/modules through gzip compression.
Selecting Which Chunks to Display
When opened, the report displays all of the Webpack chunks for your project. It's possible to filter to a more specific list of chunks by using the sidebar or the chunk context menu.
Sidebar
The Sidebar Menu can be opened by clicking the
>
button at the top left of the report. You can select or deselect chunks to display under the 'Show chunks' heading there.Chunk Context Menu
The Chunk Context Menu can be opened by right-clicking or
Ctrl
-clicking on a specific chunk in the report. It provides the following options:- Hide chunk: Hides the selected chunk
- Hide all other chunks: Hides all chunks besides the selected one
- Show all chunks: Un-hides any hidden chunks, returning the report to its initial, unfiltered view
Troubleshooting
I don't see gzip
or parsed
sizes, it only shows stat
size
It happens when
webpack-bundle-analyzer
analyzes files that don't actually exist in your file system, for example when you work with webpack-dev-server
that keeps all the files in RAM. If you use webpack-bundle-analyzer
as a plugin you won't get any errors, however if you run it via CLI you get the error message in terminal:To get more information about it you can read issue #147.
Maintainers
Yuriy Grunin | Vesa Laakso |
Contributing
Check out CONTRIBUTING.md for instructions on contributing :tada: