Three simple steps
How to use this tool?
This free online converter translates JavaScript source code into Kotlin in three simple steps.
- Step 1
Add your JavaScript code
Type, paste, or upload the JavaScript code you want to translate.
- Step 2
Convert the code
Click Convert to translate the source code into Kotlin.
- Step 3
Review the result
Review, copy, or download the resulting Kotlin code from the output editor.
See it in action
Examples of JavaScript to Kotlin conversion
These examples show JavaScript source code and the corresponding Kotlin translation. Generated results can vary as AI models are updated.
Example 1
Is String Palindrome
Program that checks if a string is a palindrome or not.
JavaScript code
Kotlin code
Example 2
Even or Odd
A well commented function to check if a number if odd or even.
JavaScript code
Kotlin code
Language comparison
Key differences between JavaScript and Kotlin
| Characteristic | JavaScript | Kotlin |
|---|---|---|
| Syntax | JavaScript has a C-style syntax with curly braces, semicolons, and parentheses. It also supports functional programming constructs like anonymous functions and closures. | Kotlin has a similar syntax to Java, but with some added features like null safety and extension functions. It also supports functional programming constructs like lambdas and higher-order functions. |
| Paradigm | JavaScript is a multi-paradigm language that supports both object-oriented and functional programming styles. | Kotlin is a multi-paradigm language that supports both object-oriented and functional programming styles. It also has some features that make it a good fit for reactive programming. |
| Typing | JavaScript is a dynamically typed language, which means that variable types are determined at runtime. | Kotlin is a statically typed language, which means that variable types are determined at compile time. It also has support for type inference. |
| Performance | JavaScript is generally slower than compiled languages like Kotlin, but it has improved significantly with the introduction of new technologies like WebAssembly. | Kotlin is a compiled language that can be optimized for performance. It also has some features that make it a good fit for building high-performance applications. |
| Libraries and frameworks | JavaScript has a vast ecosystem of libraries and frameworks, including popular ones like React, Angular, and Vue. | Kotlin has a growing ecosystem of libraries and frameworks, including popular ones like Spring and Ktor. |
| Community and support | JavaScript has a large and active community with many resources available for learning and development. | Kotlin has a growing community with many resources available for learning and development. It is also backed by JetBrains, a company that provides tools and support for developers. |
| Learning curve | JavaScript has a relatively low learning curve, especially for developers who are already familiar with C-style syntax. | Kotlin has a moderate learning curve, especially for developers who are already familiar with Java or other JVM languages. |
Common questions
Frequently Asked Questions
How do I convert JavaScript to Kotlin?
Paste your JavaScript code into the input box, confirm the languages are set to JavaScript and Kotlin, and click Convert. CodeConvert AI analyzes your JavaScript code and generates equivalent Kotlin code in seconds, preserving the original logic and structure.
What are the main differences between JavaScript and Kotlin?
JavaScript and Kotlin differ in syntax, type system, standard libraries, and common idioms, so copying code line for line usually will not compile. The converter maps each JavaScript construct to its closest Kotlin equivalent. See the comparison table below for the key differences between JavaScript and Kotlin.
Is the converted Kotlin code accurate?
The AI produces high-quality Kotlin code that preserves the behavior of your original JavaScript code and follows Kotlin conventions. It handles common patterns, data structures, and idioms for both JavaScript and Kotlin. For large or performance-critical code, review and test the Kotlin output before using it in production.
Can I convert an entire JavaScript project to Kotlin?
You can convert JavaScript files one at a time by pasting each file's code. For a full migration, convert each file and then review how classes, dependencies, and project structure map from JavaScript to Kotlin. Signing in for free raises the input limit to 25,000 characters per conversion for larger files.
Can I convert Kotlin back to JavaScript?
Yes. CodeConvert AI converts in both directions, so you can convert Kotlin to JavaScript just as easily using our Kotlin to JavaScript converter. Try the Kotlin to JavaScript Converter
Is the JavaScript to Kotlin converter free, and do I need to install anything?
Yes, it is free and runs in your browser with nothing to install and no IDE extension required. You can convert JavaScript to Kotlin without an account for up to 2 conversions per day. Sign in for free for higher limits.
What are the benefits of signing in?
Signing in unlocks CodeConvert AI's Pro converter with more powerful AI models, a built-in chat assistant, code execution, saved conversion history, and personal notes. Every free account includes 5 credits and supports up to 25,000 characters of input per conversion, with no credit card required.
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