JavaScript Interview Questions & Assessment
Evaluate JavaScript proficiency including ES6+ features, closures, prototypal inheritance, async patterns, and DOM manipulation.
Why JavaScript Matters
JavaScript powers the web — it runs in every browser and, with Node.js, on servers too. Full-stack JavaScript developers are among the most versatile engineers in the market.
Sample Interview Questions
Explain the event loop in JavaScript. How do microtasks and macrotasks differ?
What is the difference between var, let, and const? Explain hoisting behavior for each.
Implement a debounce function from scratch. Explain when you'd use debounce vs throttle.
How does prototypal inheritance work? How does it differ from classical inheritance?
Explain closures with a practical example. What are common memory leak patterns with closures?
How to Prepare
Understand the event loop, call stack, and task queue inside-out
Master ES6+ features: destructuring, spread, arrow functions, modules
Know Promise patterns, async/await, and error handling
Understand scope, closures, and the "this" keyword in different contexts
Practice with both browser and Node.js environments
Related Skills
Start practicing
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