You can compile existing Flutter code written in Dart into a web experience because it is exactly the same Flutter framework and web is just another device target for your app.
Read moreHow Flutter code is compiled?
Source: Based on Flutter System Architecture Using the Dart language allows Flutter to compile the source code ahead-of-time to native code. The engine’s C/C++code is compiled with Android’s NDK or iOS’ LLVM . Both pieces are wrapped in a “runner” Android and iOS project, resulting in an apk or ipa file respectively.29 Nis 2019
Read moreWhat can I do with Dart and Flutter?
Dart is not only used for mobile app development but is a programming language. Approved as a standard by Ecma (ECMA-408), it’s used to build just about anything on the web, servers, desktop and of course, mobile applications (Yes, the same people who standardized our favorites ES5 and ES6.)4 Mar 2019
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