JetBrains Compose Multiplatform

Name: JetBrains Compose Multiplatform
Author: Alex Park

JetBrains Compose Multiplatform enables Kotlin code sharing for UI across desktop and web platforms.

jetbrains.com

Code & Development

AP Reviewed by Alex Park, Editor — Developer Tools · Last updated May 2026

Visit JetBrains Compose Multiplatform →

TL;DR

What it does: JetBrains Compose Multiplatform enables Kotlin code sharing for UI across desktop and web platforms.
Best for: Cross-platform desktop applications.
Pricing: Visit official site — see latest tiers.

What is JetBrains Compose Multiplatform?

JetBrains Compose Multiplatform is a declarative UI toolkit for Kotlin that allows developers to write UI code once and share it across multiple platforms, including desktop (Windows, macOS, Linux) and the web. It extends the JetBrains Compose library, originally developed for Android, to enable cross-platform UI development without relying on native UI toolkits for each target. This means a single codebase can render user interfaces that function consistently on different operating systems and web browsers.

The toolkit integrates with the Kotlin Multiplatform Mobile (KMM) strategy, facilitating the sharing of UI logic alongside business logic. Developers can build applications with a unified look and feel, reducing development time and maintenance overhead. It provides a modern approach to UI development, emphasizing composable functions that describe UI elements and their state. This declarative paradigm simplifies complex UI structures and animations.

While the core Compose Multiplatform library is open-source, it is developed and maintained by JetBrains. The integration with JetBrains' IDEs, like IntelliJ IDEA, offers a familiar and efficient development experience for Kotlin developers. The focus is on enabling Kotlin developers to create native-like user experiences for desktop and web applications from a single source of truth, streamlining the path to multi-platform deployment.

Key features

Declarative UI toolkit
Kotlin-based
Desktop target support
Web target support
Code sharing
JetBrains IDE integration
Composable functions

Use cases

Cross-platform desktop applications.
Web applications using Kotlin/JS.
Sharing UI logic with Android apps.
Internal tools and utilities.
Prototyping multi-platform user interfaces.

Pros & cons

Pros

Share UI code across desktop and web.
Uses Kotlin, a modern and concise language.
Declarative UI paradigm simplifies development.
Strong IDE support from JetBrains.
Reduces development time and cost.

Cons

Not open source (developed by JetBrains).
Web support is still maturing.
Desktop support may have platform-specific nuances.
Learning curve for developers new to declarative UI.
Ecosystem is newer compared to native frameworks.

FAQ

What is JetBrains Compose Multiplatform?

It's a declarative UI toolkit for Kotlin that allows developers to share UI code across desktop (Windows, macOS, Linux) and web platforms.

What is the pricing for JetBrains Compose Multiplatform?

The core Compose Multiplatform library is open-source. JetBrains offers IDEs and other tools which may have associated costs or licensing.

Who is JetBrains Compose Multiplatform for?

It is primarily for Kotlin developers looking to build cross-platform applications for desktop and web with a single UI codebase.

What are the alternatives to JetBrains Compose Multiplatform?

Alternatives include Java Swing/JavaFX for desktop, Electron for cross-platform desktop apps, and React/Vue/Angular for web development.

Are there any technical limitations?

Web support is newer and may have limitations compared to mature web frameworks. Performance on specific desktop platforms might require tuning.