isNumber

Using

This function determines whether the given value is a valid, finite primitive number.

• Returns true if the value is a finite number (not NaN, Infinity, or -Infinity).
• Returns false for non-number types or special numeric values.

Demo - use JSON

isNumber(
 
)

true

Arguments

Argument	Type	Description	Example
value	unknown	Can be any type	"text" 2 undefined

Returns

boolean — true if value is a finite number, false otherwise

Examples

isNumber(42);
// true

isNumber(0);
// true

isNumber(-3.14);
// true

isNumber('42');
// false

isNumber(NaN);
// false

isNumber(Infinity);
// false

isNumber(new Number(5));
// false

isNumber(() => {});
// false

isNumber(undefined);
// false

Resources

📦 Since:1.3.0

📦 Last updated:1.3.0

📦 Available in:1.3.0

Source codeCode sandbox