JS-Confuser vs ProGuard

JS-Confuser obfuscates JavaScript to make source code harder to understand, copy, reuse, or modify while preserving its functionality. Its browser playground accepts pasted code, lets users choose settings, and produces a downloadable result. The playground runs in the browser, including offline, and says it does not send code or actions to a remote server. Users can start with Low, Medium, or High presets or create custom configurations. Options include renaming variables, concealing strings, flattening control flow, inserting dead code, setting domain or date locks, and tamper protection. The API offers JSConfuser.obfuscate for source code and JSConfuser.obfuscateAST for Babel ASTs; output targets include Browser and Node.js. The editor includes Prettier and a JSON representation of JSConfuser.ts settings. JS-Confuser is described by its maker as free and open source. Obfuscation can increase file size and performance overhead or break a program, and it cannot prevent determined reverse engineers from recovering code or sensitive information. Tamper protection requires eval and non-strict mode.

ProGuard is a free, open-source command-line tool for shrinking Java bytecode and optimizing code. It processes Java class files by removing unused classes, fields, methods, attributes, and instructions, then renaming remaining classes, fields, and methods with short meaningless names. It also preverifies code, producing smaller and faster applications and libraries. Guardsquare describes ProGuard as suitable for Java and Kotlin apps in mobile, embedded, and desktop environments. Build setup is documented for Android Gradle, Java or Kotlin Gradle, Ant, and Maven projects, and Android's default shrinker, R8, is compatible with ProGuard configuration. ProGuard Playground lets developers experiment with and share keep rules without rebuilding an app. ProGuardCORE is a separate free, open-source library for reading, writing, analyzing, and processing Java bytecode, including Kotlin metadata. Library jars or equivalent paths must be specified as inputs, and ProGuard leaves those libraries unchanged. Code called dynamically through reflection may need to be declared as an entry point in configuration. ProGuard runs on Android, Linux, macOS, and Windows.