JavaScript Conditional Statements Explained

Conditional statements in JavaScript are used to make decisions based on conditions. They help execute different blocks of code depending on whether a condition is true or false.

1. if Statement

Runs the code only if the condition is true.

Example:

let age = 20;

if (age >= 18) {
  console.log("You are eligible to vote.");
}

Output

2. if...else Statement

Executes one block if true, another if false.

Example:

let isRaining = false;

if (isRaining) {
  console.log("Take an umbrella.");
} else {
  console.log("No need for an umbrella.");
}

Output

3. if...else if...else Statement

Checks multiple conditions in order.

Example:

let score = 75;

if (score >= 90) {
  console.log("Grade: A");
} else if (score >= 70) {
  console.log("Grade: B");
} else {
  console.log("Grade: C or below");
}

Output

4. switch Statement

Used to test multiple values against a single variable.

Example:

let day = 3;

switch (day) {
  case 1:
    console.log("Monday");
    break;
  case 2:
    console.log("Tuesday");
    break;
  case 3:
    console.log("Wednesday");
    break;
  default:
    console.log("Another day");
}

Output