This article explores two key approaches to working with **BigDecimal big numbers in JavaScript**: using the built-in **BigInt** feature for large integers and leveraging the “**decimal.js**” library for precise decimal arithmetic.

**What is JavaScript BigDecimal?**

In JavaScript, there is no native **“BigDecimal” **data type like you might find in some other programming languages, such as Java. JavaScript primarily uses the **“number”** data type to represent both integer and floating-point numbers.

This means that JavaScript’s built-in number type has limitations when it comes to precision, especially when working with very large or very small numbers.

If you need precise decimal arithmetic in JavaScript, you often have to rely on third-party libraries or implement your own custom solutions.

One popular library for arbitrary-precision decimal arithmetic in JavaScript is **“decimal.js.”** This library allows you to perform mathematical operations with a high degree of precision.

**What is an example of a BigDecimal?**

Here’s an example of how you might use the **“decimal.js”** library to work with **BigDecimal-like numbers in JavaScript**:

First, include the library in your project:

**<script src="decimal.js"></script>
**

Then, you can use it in your JavaScript code:

**// Import the Decimal class from the library
const Decimal = require('decimal.js');
// Create BigDecimal-like numbers
const num1 = new Decimal('10.12345678901234567890');
const num2 = new Decimal('5.67890123456789012345');
// Perform arithmetic operations
const sum = num1.plus(num2);
const product = num1.times(num2);
console.log('Sum:', sum.toString());
console.log('Product:', product.toString());
**

This way, you can work with arbitrary precision decimal numbers in JavaScript using the **“decimal.js”** library, which provides functionality similar to **BigDecimal **in other programming languages.

**How to get big numbers in JavaScript?**

In JavaScript, you can represent and work with big numbers (numbers with arbitrary precision) using libraries like **“BigInt” **and **“decimal.js.”** These libraries allow you to perform mathematical operations with large and precise numbers.

Here’s how to use both of these libraries to work with big numbers:

**Using BigInt**:**BigInt**is a built-in JavaScript feature that allows you to work with arbitrarily large integers.

** // Creating BigInt values
const bigInt1 = BigInt("1234567890123456789012345678901234567890");
const bigInt2 = BigInt(9876543210987654321098765432109876543210);
// Performing arithmetic operations
const sum = bigInt1 + bigInt2;
const product = bigInt1 * bigInt2;
console.log("Sum:", sum.toString());
console.log("Product:", product.toString());**

BigInts are integers, so they are best suited for operations that involve whole numbers.

**Using decimal.js**: If you need to work with big numbers that have decimal points and require high precision, you can use the “decimal.js” library as mentioned in the previous answer.

Here’s a quick example:

** // Import the Decimal class from the library
const Decimal = require('decimal.js');
// Create Decimal objects
const num1 = new Decimal('1234567890.123456789012345678901234567890');
const num2 = new Decimal('9876543210.987654321098765432109876543210');
// Perform arithmetic operations
const sum = num1.plus(num2);
const product = num1.times(num2);
console.log('Sum:', sum.toString());
console.log('Product:', product.toString());**

**“decimal.js”** provides arbitrary-precision decimal arithmetic, which is useful when you need to work with numbers that have both integer and fractional parts and require precise calculations.

Choose the library that best suits your needs based on whether you’re working with integers** (BigInt) **or decimal numbers with high precision **(“decimal.js”)**.

**Conclusion**

When you encounter scenarios in **JavaScript **that demand the manipulation of **big numbers**, you have options to address the challenge.

For dealing with large integers, the **native BigInt feature** is a powerful tool, allowing you to work with arbitrarily large whole numbers efficiently.

On the other hand, if your requirements involve both integer and fractional parts with high precision, “decimal.js” is a valuable library that brings the flexibility of **BigDecimal**-like arithmetic to JavaScript.

By understanding and using these tools, you can confidently tackle numerical challenges in your JavaScript applications, no matter how big or precise the numbers may be.