Flutter apps are too big in size

One way that i use to reduce my app size is to use;

flutter clean

before i run the build command;

flutter build appbundle --target-platform android-arm,android-arm64

When i run the build command without the clean command, i get around 32mb, but if i run the clean command first, i get around 18mb

Flutter team acknowledges it here.

There's an explanation for this here, quoting the same -

In August 2018, we measured the size of a minimal Flutter app (no Material Components, just a single Center widget, built with flutter build apk), bundled and compressed as a release APK, to be approximately 4.7MB.

For this simple app, the core engine is approximately 3.2MB (compressed), the framework + app code is approximately 840KB (compressed), the LICENSE file is 55KB (compressed), necessary Java code (classes.dex) is 57KB (compressed), and there is approximately 533KB of (compressed) ICU data.

Of course, YMMV, and we recommend that you measure your own app, by running flutter build apk and looking at build/app/outputs/apk/release/app-release.apk.

Also, the relative differences in apk size would likely be smaller with larger apps. Flutter's overhead size is fixed.

Yes ofcourse, the size of the apk or ipa built with flutter will be minimum of ~7mb for a hello world app. This is because, flutter ships a core engine, framework, ICU data, LICENSE file etc with its build output which are mandatory for a flutter app to run.

You can check out the FAQ here to know more about what takes how much size when build.

Hope that helps!