JavaScript Scope & Hoisting - Practice Questions 2026

Mastering JavaScript requires more than just reading syntax; it requires a deep understanding of how the engine handles data and execution. These JavaScript Scope & Hoisting Practice Questions are designed to bridge the gap between theoretical knowledge and technical interview readiness. By focusing on the "under the hood" mechanics of JavaScript, this course ensures you won't be caught off guard by tricky code snippets or complex closures.

Why Serious Learners Choose These Practice Exams

Serious learners choose this course because it moves beyond surface-level definitions. While many tutorials explain what a variable is, few challenge you to predict the behavior of that variable within nested scopes or during the creation phase of an execution context. These exams provide:

• Deep Technical Insight: Understand the "why" behind every result.

Course Structure

The curriculum is meticulously organized to take you from foundational logic to professional-grade problem-solving.

• Basics / Foundations

This section focuses on the fundamental declaration types: var, let, and const. You will learn the primary differences in how these keywords interact with the global object and their initial values.

Here, we dive into Global and Function scope. You will practice identifying where variables are accessible and how the JavaScript engine searches for identifiers within a single level of scope.

This module introduces Block scope and the Temporal Dead Zone (TDZ). You will learn how modern JavaScript prevents common errors by restricting variable access before declaration.

Focus on nested scopes, Lexical Environment, and Closures. This section challenges your ability to track variable values across multiple function calls and execution contexts.

Test your knowledge against "dirty" code. These questions simulate real-world debugging scenarios where scope leaks or hoisting issues lead to unexpected production bugs.

A comprehensive exam that blends all previous topics. This mimics a high-pressure interview environment where you must switch between different conceptual frameworks rapidly.

Sample Practice Questions

QUESTION 1

What will be the output of the following code?

JavaScript

console.log(a);

var a = 10;

• OPTION 1: 10

• Option 2: Wrong because var is hoisted; a ReferenceError only occurs if the variable was never declared.

QUESTION 2

What occurs in this block?

JavaScript

{

  console.log(b);

  let b = 20;

}

• OPTION 1: 20

• Option 1: Wrong because let does not allow access before the line of declaration.

QUESTION 3

Which scope does a variable declared with var inside an if block belong to?

• OPTION 1: Block Scope

• Option 1: Wrong because only let and const respect block boundaries.

Welcome to the best practice exams to help you prepare for your JavaScript Scope & Hoisting - Practice Questions.

• You can retake the exams as many times as you want

We hope that by now you're convinced! And there are a lot more questions inside the course.