rn-size-check v0.3.0: compare two builds

What grew between two builds?

npx rn-size-check compare old.aab new.aab

• New compare command. Each side can be a build (.aab/.apk) or a report saved with --json.
• Shows the change in download, install and file size, per category, the files that were added, removed, grew or shrank, and the npm packages that changed (when both builds have source maps).
• Lists problems that are new, fixed, got worse (10 → 11 big PNGs) or got better.
• --markdown size.md writes a PR comment, --json saves the comparison, and --max-growth <MB> exits with code 1 when the download grows too much (for CI).
• The website has a Compare page: drop the old and the new build (or two saved reports). Still read in your browser.
• Saved reports now include the full file list, so two reports can be compared file by file. Reports from older versions still compare by category.

npx rn-size-check@latest android/app/build/outputs/bundle/release/app-release.aab

📦 npm: https://www.npmjs.com/package/rn-size-check · 🌐 Web: https://rn-size-check-web.vercel.app

rn-size-check v0.2.1: just run npx rn-size-check --project

• The build path is optional. Run inside the project and it picks the newest release .aab or .apk in android/app/build/outputs (flavors too), so the whole command is npx rn-size-check --project.
• A wrong build path now points to the release build the project does have (for example the .aab when you typed .apk).
• The icon-fonts fix lists the icon fonts your code uses (for example iconFontNames: [ "Ionicons.ttf", "MaterialCommunityIcons.ttf" ]) instead of a fixed example.
• The npm package table ends with a total, and shows how big the bundle is in the download, so the unpacked bytecode numbers don't look like they disagree with the breakdown.
• --project works without a folder and then uses the current one, so npx rn-size-check app-release.aab --project run inside the project just works (it used to fail with "argument missing").

npx rn-size-check@latest android/app/build/outputs/bundle/release/app-release.aab

📦 npm: https://www.npmjs.com/package/rn-size-check · 🌐 Web: https://rn-size-check-web.vercel.app

rn-size-check v0.2.0: which npm package makes your app big

Which npm packages make the JS bundle big? Point the tool at your React Native project, or drop the source maps on the website:

npx rn-size-check app-release.apk --project .

• npm package breakdown of the JS bundle from React Native's own Gradle source maps, in real Hermes bytecode bytes (each position in the composed map is a byte offset in the bytecode). Also shows your app code, JSON compiled into the bundle, and Hermes's string and data tables.
• The maps are checked against the build: a map from a different build, or a Hermes map with a plain JS bundle, is refused with a clear message instead of showing wrong numbers.
• Lottie animations the code require()s are now found (from the packager map), with an estimate of their download cost.
• Exact unused fonts: with a map, font-weights and icon-fonts report exactly which files no code references, with exact savings.
• New checks (need a map): heavy-package (moment, lodash, big icon libraries), duplicate-packages (one package bundled in two versions), duplicate-modules (the same file bundled twice under different paths), font-name-case (a fontFamily that differs from the font file only in letter case, which Android won't find).
• New flags: --project <dir> and --sourcemap <file>. The website accepts .map files dropped with the build, or added afterwards.
• Markdown summary includes the top packages.
• Package advice looks at the rest of the bundle: moment next to date-fns says to move to date-fns; a package your code never imports (only another dependency does) is shown as info, with npm ls advice instead of import tips.
• Fonts in res/font (Android resources used by native libraries) are never reported as unused; only assets/fonts is judged against the JS code.

npx rn-size-check@latest android/app/build/outputs/bundle/release/app-release.aab

📦 npm: https://www.npmjs.com/package/rn-size-check · 🌐 Web: https://rn-size-check-web.vercel.app

rn-size-check v0.1.3: Lottie animation check

• New check lottie-large: finds Lottie animations shipped in res/raw or assets that are over 100 KB unpacked or have images embedded inside (base64 PNG/JPG). Embedded images are flagged as a warning because they barely compress; big vector-only animations are flagged as info because they compress well but are still parsed at full size. Recognises both After Effects (Bodymovin) and LottieFiles exports. Suggested by a reader of the launch post.
• Markdown summary: savings read "· saves 54 KB" instead of a second set of brackets.

npx rn-size-check@latest android/app/build/outputs/bundle/release/app-release.aab

📦 npm: https://www.npmjs.com/package/rn-size-check · 🌐 Web: https://rn-size-check-web.vercel.app

rn-size-check v0.1.2: Play Console units, font weights check

Found by checking a real release APK against Play Console and the app source.

• Sizes now use decimal MB (1 MB = 1,000,000 bytes), the same as Google Play Console. A 48,776,475-byte APK now shows 48.8 MB instead of 46.5. --budget uses the same units.
• New check font-weights: flags one font family shipped with many weights and italics (for example 14 Rubik files when the app uses 5).
• ABI advice is safer: the universal-APK finding now says not to delete armeabi-v7a (32-bit phones need it) and to give each phone only its own ABI with an AAB or ABI splits.
• npm page links to the website.

npx rn-size-check@latest android/app/build/outputs/bundle/release/app-release.aab

📦 npm: https://www.npmjs.com/package/rn-size-check · 🌐 Web: https://rn-size-check-web.vercel.app

rn-size-check v0.1.1: accuracy fixes

Accuracy fixes found by checking real app reports against their source.

• Install size respects extractNativeLibs. Since minSdk 23 native libraries are loaded straight from the APK, so no unpacked copy is added (a 46.5 MB APK was reported as 62.6 MB installed).
• icon-fonts only flags the full default react-native-vector-icons set (12+ fonts). A trimmed iconFontNames list is no longer reported.
• Markdown summary labels the JS bundle "(Hermes)".
• Debug builds no longer show a savings total.
• A missing or unreadable file gives a clear error instead of a crash.
• New zip reader (no native dependencies); the same engine now powers the website: https://rn-size-check-web.vercel.app

npx rn-size-check@latest android/app/build/outputs/bundle/release/app-release.aab

📦 npm: https://www.npmjs.com/package/rn-size-check · 🌐 Web: https://rn-size-check-web.vercel.app

rn-size-check v0.1.0: first release 🎉

Find out why your React Native app is big, and how to shrink it.

npx rn-size-check android/app/build/outputs/bundle/release/app-release.aab

What it does

• Size breakdown of an Android .aab / .apk: JS/Hermes bundle, native libraries, Java/Kotlin code, images, fonts
• Realistic download size for one phone (one ABI and screen density, like Google Play delivers)
• App info from the manifest: package, version, minSdk, Hermes version, R8 on/off

9 checks, with the files involved and MB savings

Debug build, universal APK with every ABI, unstripped native libraries, source maps shipped, R8 off, Hermes off, large PNG/JPEG, all vector-icon fonts bundled, duplicate files.

For CI

--json report, --budget <MB> fails the build when the app grows too big, --format plain for logs.

Private

Runs locally; your build is never uploaded.

Android only for now; iOS is planned. Feedback and issues welcome!

📦 npm: https://www.npmjs.com/package/rn-size-check