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Free Swift to Kotlin Converter

Translate Swift into Kotlin code with a click of a button

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Three simple steps

How to use this tool?

This free online converter translates Swift source code into Kotlin in three simple steps.

  1. Step 1

    Add your Swift code

    Type, paste, or upload the Swift code you want to translate.

  2. Step 2

    Convert the code

    Click Convert to translate the source code into Kotlin.

  3. Step 3

    Review the result

    Review, copy, or download the resulting Kotlin code from the output editor.

See it in action

Examples of Swift to Kotlin conversion

These examples show Swift 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.

Swift code

Kotlin code

Example 2

Even or Odd

A well commented function to check if a number if odd or even.

Swift code

Kotlin code

Language comparison

Key differences between Swift and Kotlin

Key differences between Swift and Kotlin
CharacteristicSwiftKotlin
SyntaxSwift has a syntax that is similar to many other modern programming languages, with a focus on readability and simplicity.Kotlin has a syntax that is also similar to many modern programming languages, with a focus on conciseness and expressiveness.
ParadigmSwift is a multi-paradigm language that supports both object-oriented and functional programming.Kotlin is a multi-paradigm language that supports both object-oriented and functional programming.
TypingSwift is a statically-typed language, meaning that variable types are checked at compile-time.Kotlin is a statically-typed language, meaning that variable types are checked at compile-time.
PerformanceSwift is known for its high performance, as it is designed to be fast and efficient.Kotlin is also known for its good performance, although it may not be as optimized as Swift in some cases.
Libraries and frameworksSwift has a rich ecosystem of libraries and frameworks, including popular ones like SwiftUI and Alamofire.Kotlin has a growing ecosystem of libraries and frameworks, with popular ones like Ktor and Anko.
Community and supportSwift has a large and active community, with good support from Apple and a dedicated website for documentation and resources.Kotlin also has a growing community, with support from JetBrains and a dedicated website for documentation and resources.
Learning curveSwift has a relatively steep learning curve, especially for beginners with no prior programming experience.Kotlin has a relatively gentle learning curve, especially for developers familiar with Java or other similar languages.

Common questions

Frequently Asked Questions

How do I convert Swift to Kotlin?

Paste your Swift code into the input box, confirm the languages are set to Swift and Kotlin, and click Convert. CodeConvert AI analyzes your Swift code and generates equivalent Kotlin code in seconds, preserving the original logic and structure.

What are the main differences between Swift and Kotlin?

Swift 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 Swift construct to its closest Kotlin equivalent. See the comparison table below for the key differences between Swift and Kotlin.

Is the converted Kotlin code accurate?

The AI produces high-quality Kotlin code that preserves the behavior of your original Swift code and follows Kotlin conventions. It handles common patterns, data structures, and idioms for both Swift and Kotlin. For large or performance-critical code, review and test the Kotlin output before using it in production.

Can I convert an entire Swift project to Kotlin?

You can convert Swift 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 Swift 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 Swift?

Yes. CodeConvert AI converts in both directions, so you can convert Kotlin to Swift just as easily using our Kotlin to Swift converter. Try the Kotlin to Swift Converter

Is the Swift 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 Swift to Kotlin without an account for up to 5 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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