30-seconds-of-code/snippets/is-number.md

title, type, tags, cover, dateModified

title	type	tags	cover	dateModified
Value is number	snippet	type math	red-petals	2020-09-15T16:28:04+03:00

Checks if the given argument is a number.

• Use typeof to check if a value is classified as a number primitive.
• To safeguard against NaN, check if val === val (as NaN has a typeof equal to number and is the only value not equal to itself).

const isNumber = val => typeof val === 'number' && val === val;

isNumber(1); // true
isNumber('1'); // false
isNumber(NaN); // false