is-number

What is is-number?

The is-number npm package is a simple utility for checking if a value is a number. It works with various types of numeric representations, including strings that can be coerced to numbers, and provides a straightforward API for determining if a value can be considered a number in JavaScript.

What are is-number's main functionalities?

Check if a value is a number

This feature allows you to check if a value is a number, including numeric strings.

const isNumber = require('is-number');

console.log(isNumber(5)); // true
console.log(isNumber('5')); // true
console.log(isNumber('five')); // false

Check if a value is not a number

This feature allows you to check if a value is not a number, including strings that cannot be coerced to numbers and other non-numeric types.

const isNumber = require('is-number');

console.log(isNumber('foo')); // false
console.log(isNumber([1, 2, 3])); // false

Check if a value is a finite number

This feature allows you to check if a value is a finite number, excluding Infinity, -Infinity, and NaN.

const isNumber = require('is-number');

console.log(isNumber(Infinity)); // false
console.log(isNumber(-Infinity)); // false
console.log(isNumber(NaN)); // false

Other packages similar to is-number

isnumeric

The isnumeric package offers similar functionality to is-number by checking if a value is numeric. It is similar in its simplicity and direct approach.

numerable

The numerable package is a more comprehensive library for number validation and formatting. It provides additional functionality compared to is-number, such as parsing and formatting numbers with localization support.

validate.io-number-primitive

This package is part of the validate.io suite and checks if a value is a number primitive. It is more strict than is-number as it does not consider numeric strings to be numbers.