Tutorials & Books

 For beginners

freeCodeCamp beginner tutorials

Free

freeCodeCamp provides tens of thousands of hours worth of free learning material for programmers. This includes a Kotlin tutorial for beginners, in both text and video form.

Exploring Kotlin

Free - 25

A straight and to-the-point explanation of Kotlin's syntax and features (including sample code) condensed into a 100-page book, and you can pay what you want - including nothing! This is not a deep dive, but should be plenty of information to get any beginner started.

Kotlin Programming By Example

40 - 50

If you're already familiar with computers and how they work, then this Android-oriented book might not be a bad match for you. While a little terse when it comes to the fundamentals, it provides a relatively comprehensive tour of Kotlin's basics, and teaches many related technologies through three separate projects.

Kotlin Apprentice

30 - 60

Kotlin Apprentice is a book for complete beginners, designed to ease you into the basic concepts of programming before teaching you the fundamentals of Kotlin. It also covers many advanced features of the language, such as functional programming, operator overloading and coroutines.

 For Android developers

Kotlin Koans

Free

A series of exercises intended to get developers familiar with the Kotlin syntax and some idioms, provided by JetBrains for free.

Kotlin Koans is also available directly from within IntelliJ IDEA Edu or Android Studio.

Android Developers: Kotlin resources

Free

A short crash-course on Kotlin, plus a set of Kotlin learning resources recommended by Google themselves, specifically intended to bring existing Android developers up to speed with Kotlin.

 For Java developers

Kotlin Koans

Free

A series of exercises intended to get developers familiar with the Kotlin syntax and some idioms, provided by JetBrains for free.

Kotlin Koans is also available directly from within IntelliJ IDEA Edu or Android Studio.

Getting Started with Kotlin

Free

An official JetBrains guide to getting started with Kotlin using IDEA, Eclipse, or the command-line compiler. It also introduces the basics of running code snippets and working with build tools.

Google I/O: Introduction to Kotlin

Free

A short primer on what you can expect from Kotlin when compared with Java. This talk took place at Google I/O 2017, and is presented by Hadi Hariri, VP of Developer Advocacy at JetBrains.

Google I/O: How to Kotlin

Free

Another short primer on what you can expect from Kotlin when compared with Java. This talk took place at Google I/O 2018, and is presented by Andrey Breslav, the lead Kotlin language designer.

This video covers more advanced topics than the 2017 talk above.

 For Python developers

Kotlin Koans

Free

A series of exercises intended to get developers familiar with the Kotlin syntax and some idioms, provided by JetBrains for free.

Kotlin Koans is also available directly from within IntelliJ IDEA Edu or Android Studio.

Kotlin for Python developers

Free

A tutorial written by Aasmund Eldhuset and owned by Khan Academy which, despite not being a part of Khan Academy's official product catalogue, provides an excellent primer for getting started with Kotlin if you already know Python.

This tutorial is part of the tutorials section of the official Kotlin docs.