Off By One

Daily coding puzzles to sharpen your debugging skills

Every developer knows that feeling: staring at code that should work but doesn't. The logic seems sound, the syntax is correct, but there's something... off.

Off By One turns debugging into a daily game.

Each day, we present you with a new coding puzzle featuring real bugs hidden in code snippets. Your mission: spot the bug before it spots you. Train your eye for the subtle errors that cause the biggest headaches.

🎯 What you'll practice:

• •Spot off-by-one errors, null pointer exceptions, and logic bugs
• •Debug code across JavaScript, Python, and Java
• •Build pattern recognition for common programming mistakes
• •Compete with developers worldwide on daily leaderboards

🚀 Features:

• •New daily puzzles across multiple programming languages
• •Anonymous leaderboards to track your debugging speed
• •Personal statistics and progress tracking
• •Privacy-first design with anonymous authentication

Whether you're a junior developer building your debugging intuition or a senior engineer keeping your skills sharp, Off By One offers a fun, low-pressure way to practice one of programming's most essential skills.

Because the best debuggers aren't born—they're trained.

One puzzle at a time.