Number

`Number.prototype.toExponential`

Returns a string representing the Number object in exponential notation

Syntax

JavaScript

number.toExponential(fractionDigits?)

Parameters

Parameter	Type	Description
fractionDigits	number	Number of digits after the decimal point (0-100)

Return Value

A string representing the number in exponential notation

Examples

Basic Usage

const num = 123456;
console.log(num.toExponential()); // '1.23456e+5'
console.log(num.toExponential(2)); // '1.23e+5'

Practical Example

console.log((0.00123).toExponential()); // '1.23e-3'
console.log((77.1234).toExponential(4)); // '7.7123e+1'

Advanced Usage

const avogadro = 6.022e23;
console.log(avogadro.toExponential(3)); // '6.022e+23'

Understanding Number.prototype.toExponential

The Number.prototype.toExponential method in JavaScript returns a string representing the Number object in exponential notation. It belongs to the Number object and is one of the most widely used methods for working with number values in modern JavaScript and TypeScript applications.

The method signature is number.toExponential(fractionDigits?). It accepts 1 parameter: fractionDigits. When called, it returns a string representing the number in exponential notation. Understanding when and how to use toExponential() helps you write more expressive, readable code.

Common use cases for Number.prototype.toExponential include data transformation, input validation, API response processing, and building reusable utility functions. It works well alongside related methods like number-tofixed, number-toprecision, number-tostring, enabling you to chain operations together for complex data manipulation pipelines.

Browser support for Number.prototype.toExponential is excellent across all modern browsers including Chrome, Firefox, Safari, and Edge. It is also fully supported in Node.js and Deno. For older environments, transpilation with Babel or a polyfill may be needed.