Type Conversion

Learn how to convert a value from one data type to another in JavaScript.

What is Type Conversion?

Type conversion means changing a value from one data type to another data type.

For example, a text value such as "100" can be converted into the number 100.

JavaScript type conversion and automatic coercion.

Explicit Type Conversion

In explicit conversion, the developer manually converts a value by using functions such as Number(), String(), or Boolean().

Simple Conversion Flow

Example 1: String to Number

Sometimes numbers come from forms or other sources as text. We can use Number() to convert that text into a number.

const marksText = "85";

const marks = Number(marksText);

console.log("Marks:", marks);
console.log("Type:", typeof marks);

Output

Example 2: Number to String

We can use String() when we want to convert a number into text.

const score = 95;

const scoreText = String(score);

console.log("Score:", scoreText);
console.log("Type:", typeof scoreText);

Output

Example 3: Value to Boolean

The Boolean() function converts a value into either true or false.

const courseName = "JavaScript";
const emptyValue = "";

console.log("Course Value:", courseName);
console.log("Boolean Value:", Boolean(courseName));

console.log("Empty Value:", emptyValue);
console.log("Boolean Value:", Boolean(emptyValue));

Output

Automatic Type Conversion

JavaScript can also automatically convert values during some operations. This behavior is called type coercion.