Minify Kotlin source while preserving multiline strings
Safe Kotlin MinificationTool summary
Free online Kotlin minifier to compress source code in your browser. Remove comments and whitespace while preserving strings, chars, and multiline literals.
This page accepts Kotlin source code and produces minified Kotlin source. It belongs to the MinifyTool directory of browser-based developer tools, so crawlers and answer engines can understand the input, output, options, preservation rules, and related pages without running JavaScript.
removeComments.collapseWhitespace.keepNewlines.keepIndent.preserveTriple.autoMinify.rememberInput.wrapLines.Use the Kotlin Minifier when you need minified Kotlin source from Kotlin source code. For neighboring tasks, use the related MinifyTool pages linked below.
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Paste Kotlin source code here.After
Review minified Kotlin source here.For Kotlin Android apps, choose a minifier or shrinker that understands the Android build process. APK size usually depends on compiled bytecode, resources, dependencies, native libraries, and assets, not just Kotlin source text. R8 and ProGuard-style rules are common in Android workflows. Keep rules matter when reflection, serialization, dependency injection, or annotations are used. Test a release build on real screens before shipping a smaller APK.
Kotlin minifier services for mobile development should be compared on practical features: Android integration, keep-rule support, mapping files, resource shrinking, reports, and how well they handle Kotlin metadata. A tool that only removes whitespace from `.kt` files will not do much for APK size. For mobile apps, the useful work happens after compilation. Run the app's navigation, login, networking, and crash reporting flows after any shrinking change.
Professional Android developers usually rely on build-integrated shrinkers instead of manually minifying Kotlin source. The reason is repeatability. A release build can shrink bytecode, remove unused resources, and produce mapping files every time. An online Kotlin minifier is still useful for small source examples or generated snippets. For an app in the Play Store, use the same release pipeline your team can test, reproduce, and debug.
Code shrinking in Android development means removing unused code and sometimes shortening names in the compiled app. It is different from simply deleting spaces in Kotlin source files. Shrinking can reduce APK or AAB size, but it needs rules for classes used by reflection, JSON parsing, dependency injection, or XML layouts. If the shrinker removes something that is only loaded at runtime, the app may crash. Testing release builds is essential.
A tool for obfuscating Kotlin Android apps can make class and method names harder to read in the compiled output, and it may also shrink unused code. It is not a complete security solution. Secrets should not live in the app, obfuscated or not. Keep mapping files so crash reports can be translated back into useful names. Before enabling aggressive obfuscation, test login, payments, deep links, push notifications, and serialization.
Kotlin code reduction methods include source cleanup, dependency review, bytecode shrinking, resource shrinking, and build configuration changes. Source minification is the smallest part for most Android apps. Removing an unused image set or heavy dependency may save more than compacting `.kt` files. Compare methods by measuring the final APK or AAB size. Also watch for side effects, because smaller builds are not helpful if reflection or generated code stops working.
To reduce Kotlin application size, inspect the final package first. Look at resources, dependencies, native libraries, and generated code. Then enable appropriate release shrinking, review keep rules, and remove unused assets. For example, large images in multiple densities may outweigh the Kotlin code itself. Source minification can help for snippets, but mobile app size is usually a packaging problem. Build, install, and test the release variant before publishing.