Code Output
v1.0.0Predict what real code snippets print — 45 tricky examples across JavaScript, TypeScript, Python, Go, Rust and C#. Hoisting, coercion, closures, ownership, async edge cases.
A code-prediction quiz — read a short snippet in JavaScript/TypeScript/Python/Go/Rust/C# and guess what it prints. Every question comes with a full explanation of why.
How to use- →Select a language, difficulty and category, then press Start (or Space). Each round has 10 questions.
- →Press A / B / C / D (or 1 / 2 / 3 / 4) to answer. The explanation appears immediately after each answer.
- →Enable Speed mode for a 15-second per-question timer and an extra time bonus on every correct answer.
Language
Difficulty
Category
Rounds
Speed mode (15 s)
45 snippets match your filters.
Guess the output
Read each snippet and pick what it prints. Answers are revealed with a full explanation. Correct → streak × base × multiplier. Wrong → lose a life.