Code Complete: JS Practice
Exercises with real tests
About
Practice writing JavaScript with a real editor and syntax highlighting. Run your code against tests directly on your device and receive hints and reference solutions. Learn at your own pace with a private, free, and offline experience.
What's New in Code Complete
2.0
October 21, 2026
Code Complete is back, rebuilt from scratch. • 51 new JavaScript exercises with tests that run on your device • Original progressive hints and reference solutions • A new editor with syntax highlighting, line numbers and auto-indent • Now on iPhone, iPad and Mac • Completely free: no account, ads or in-app purchases, and no data collected
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FAQ
What is Code Complete?
Code Complete is a free, offline application designed for practicing JavaScript coding. It offers a real editor with syntax highlighting and allows users to run their code against tests directly on their device.
Does Code Complete have ads?
No, Code Complete is completely ad-free. The app is designed to provide a private and uninterrupted learning experience with no advertisements.
Can I use Code Complete offline?
Yes, Code Complete is an offline application. You can practice writing and testing JavaScript code without needing an internet connection.
What kind of JavaScript exercises are available?
Code Complete offers 51 exercises covering arrays, strings, math, dynamic programming, search, data structures like linked lists and trees, and graph problems, ranging from easy to challenging.
Does Code Complete offer any learning support?
Yes, Code Complete provides up to three progressive hints per exercise, from a simple nudge to the core idea. It also includes a reference solution for comparison.
Is my code safe on Code Complete?
Your code runs in an isolated, on-device JavaScript sandbox. Infinite loops are safely stopped, and your code is never sent anywhere, ensuring privacy and security.
What devices does Code Complete support?
Code Complete is available on Mac, iPhone, and iPad, allowing you to practice JavaScript coding across multiple Apple devices.
How often is Code Complete updated?
The latest version of Code Complete is 2.0, and it was last updated on October 21, 2026. This indicates a commitment to ongoing development and improvements.