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Working with Numbers and Strings in JavaScript

By Swann
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Published on
Working with Numbers and Strings in JavaScript


JavaScript is versatile when it comes to handling different data types, especially numbers and strings. Both of these data types are fundamental in web development, whether you’re performing calculations, manipulating text, or rendering dynamic content on the web page.

Working with Numbers in JavaScript

Basic Operations

JavaScript allows performing basic arithmetic operations like addition, subtraction, multiplication, and division easily.

let a = 10;
let b = 20;

console.log(a + b); // 30
console.log(a - b); // -10

Complex Calculations

JavaScript Math object provides methods for more complex calculations like rounding, powers, and trigonometry.

console.log(Math.sqrt(25));  // 5
console.log(Math.pow(2, 3)); // 8

Working with Strings in JavaScript


Strings can be concatenated using the + operator or template literals.

let greeting = "Hello";
let name = "World";

console.log(greeting + " " + name); // Hello World
console.log(`\${greeting} \${name}`); // Hello World

Methods and Properties

JavaScript strings come with a variety of methods and properties, allowing developers to manipulate and analyze text effectively.

let text = "JavaScript is fun";

console.log(text.length);        // 17
console.log(text.toUpperCase()); // JAVASCRIPT IS FUN

Type Conversion

Implicit and explicit type conversions between strings and numbers are common in JavaScript.

let stringValue = "100";
let numberValue = 50;

// Implicit conversion
console.log(stringValue - numberValue); // 50

// Explicit conversion
console.log(Number(stringValue) + numberValue); // 150
console.log(stringValue + String(numberValue)); // 10050


Numbers and strings are foundational data types that you’ll encounter regularly when working with JavaScript. Understanding how to manipulate and operate with these data types is pivotal for creating interactive and dynamic web pages. As you progress in your JavaScript journey, combining these fundamental operations with other aspects of the language will enable you to create more complex and interactive web applications.

Additional Resources

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