@gedeagas/react-native-bundle-visualizer

See what's inside of your react-native bundle 📦

Uses the awesome source-map-explorer to visualize the output of the Metro bundler.

Purpose

Sometimes, importing a single javascript library can drastically increase your bundle size. This package helps you to identify such a library, so you can keep the bundle size low and loading times fast.

Usage

Make sure npx is installed and run the following command in your project root

npx @gedeagas/react-native-bundle-visualizer

Or install as a dev-dependency

yarn add --dev @gedeagas/react-native-bundle-visualizer

And run it:

yarn run react-native-bundle-visualizer

or when using npm:

npm install --save-dev @gedeagas/react-native-bundle-visualizer
npx react-native-bundle-visualizer

CI/CD Usage

For CI/CD environments where you need to capture just the bundle size for comparison or monitoring, use the --bundle-size-only option (outputs 3 decimal places):

# Output only the bundle size in megabytes (e.g., "2.450MB")
npx @gedeagas/react-native-bundle-visualizer --bundle-size-only

# Example: Capture bundle size in a variable
BUNDLE_SIZE=$(npx @gedeagas/react-native-bundle-visualizer --bundle-size-only)
echo "Bundle size: $BUNDLE_SIZE"

# Example: Compare bundle sizes in CI
PREV_SIZE=$(cat .bundle-size-cache 2>/dev/null || echo "0MB")
CURRENT_SIZE=$(npx @gedeagas/react-native-bundle-visualizer --bundle-size-only)
echo $CURRENT_SIZE > .bundle-size-cache

# Extract numeric values for comparison (removes "MB" suffix)
PREV_NUM=$(echo $PREV_SIZE | sed 's/MB//')
CURRENT_NUM=$(echo $CURRENT_SIZE | sed 's/MB//')

if (( $(echo "$CURRENT_NUM > $PREV_NUM" | bc -l) )); then
  echo "⚠️  Bundle size increased from $PREV_SIZE to $CURRENT_SIZE"
  exit 1
else
  echo "✅ Bundle size is $CURRENT_SIZE (was $PREV_SIZE)"
fi

Command line arguments

All command-line arguments are optional. By default a production build will be created for the ios platform.

Option	Description	Example
platform	Platform to build (default is ios)	--platform ios
dev	Dev or production build (default is false)	--dev false
entry-file	Entry-file (when omitted tries to auto-resolve it)	--entry-file ./index.ios.js
bundle-output	Output bundle-file (default is tmp)	--bundle-output ./myapp.bundle
format	Output format html, json or tsv (default is html) (see source-map-explorer options)	--format json
only-mapped	Exclude "unmapped" bytes from the output (default is false). This will result in total counts less than the file size.	--only-mapped
verbose	Dumps additional output to the console (default is false)	--verbose
reset-cache	Removes cached react-native files (default is false)	--reset-cache
--expo	Set this to true/ false based on whether using expo or not. For eg, set --expo true when using expo. Not required to pass this for react-native cli. (default is false)	--expo false
--no-border-checks	Pass the same flag to the underlying source-map-explorer to disable invalid mapping column/line checks.	--no-border-checks
--bundle-size-only	Output only the bundle size in plain megabytes with "MB" suffix (3 decimal places, e.g., "2.450MB") (useful for CI/CD environments). This will suppress all other output and return just the formatted size.	--bundle-size-only

Use react-native-bundle-visualizer@2 when targetting Expo SDK 40 or lower.

Version compatibility

Version	Comments
3.x	Compatible with React-Native CLI bootstrapped projects and Expo SDK 41 or higher.
2.x	Compatible with React-Native CLI bootstrapped projects and Expo SDK 40 or earlier.
1.x	Uses the Haul bundler instead instead of the Metro output.

License

MIT