What is JavaScript's highest integer value that a number can go to without losing precision?

JavaScript has a built-in number type called Number to represent both integers and floating-point numbers. However, integers in JavaScript have a specific limit on how large they can be without losing precision.

The Maximum Integer Value in JavaScript

The highest integer value that JavaScript can represent without losing precision is given by the Number.MAX_SAFE_INTEGER constant. It has a value of 9,007,199,254,740,991.

Here is an example:

                console.log(Number.MAX_SAFE_INTEGER); // Output: 9007199254740991

If you attempt to go beyond this value, the number may lose precision and may not be accurately represented. It's important to be aware of this limitation when working with very large numbers in JavaScript.

Loss of Precision

When you perform mathematical operations on a large integer value that exceeds the maximum safe integer value, JavaScript may introduce rounding errors and lose precision.

Here's an example:

                console.log(Number.MAX_SAFE_INTEGER + 1); // Output: 9007199254740992
                console.log(Number.MAX_SAFE_INTEGER + 2); // Output: 9007199254740992
                console.log(Number.MAX_SAFE_INTEGER + 3); // Output: 9007199254740994

As you can see, adding 1 to the maximum safe integer does not result in the expected value. This is because JavaScript rounds the number to the nearest representable value.

Different Browsers May Have Different Limits

While JavaScript itself defines the maximum safe integer value, different browsers may have different implementations and limitations.

For example, the V8 engine used by Google Chrome and Node.js can represent integers with a maximum precision of 53 bits, allowing for a maximum integer value of 9,007,199,254,740,991. However, the SpiderMonkey engine used by Firefox supports 64-bit integers, allowing for larger integer values.

It's important to consider these potential differences when developing cross-browser JavaScript applications that deal with large integers.

Handling Large Integers in JavaScript

If you need to work with large integers that exceed the maximum safe integer value, there are libraries available that provide support for arbitrary precision arithmetic.

One popular library is Big.js, which allows you to perform precise calculations with arbitrarily large numbers:

                // Import the Big.js library
                <script src="https://cdn.jsdelivr.net/npm/[email protected]/big.min.js"></script>

                // Use Big.js to perform calculations
                let a = new Big('9007199254740991');
                let b = new Big('9007199254740991');
                let sum = a.plus(b);
                console.log(sum.toString()); // Output: 18014398509481982

By using a library like Big.js, you can accurately perform calculations with very large integers in JavaScript without losing precision.


The highest integer value that JavaScript can represent without losing precision is given by Number.MAX_SAFE_INTEGER. Going beyond this value can result in rounding errors and loss of precision. Different browsers may have different limitations, so it's important to consider cross-browser compatibility when working with large integers. If you need to work with integers exceeding the maximum safe integer value, using a library like Big.js can provide support for arbitrary precision arithmetic.