isNumber (Lodash Compatibility)

::: warning Use typeof operator

This isNumber function is complex due to handling Number object wrappers.

Instead, use the simpler and modern typeof value === 'number'.

:::

Checks if a value is a number.

const result = isNumber(value);

Usage

isNumber(value)

Use isNumber when you want to check if a value is a number. This function recognizes both primitive numbers and Number objects as numbers.

import { isNumber } from 'es-toolkit/compat';

// Primitive numbers
isNumber(123);
// Returns: true

isNumber(3.14);
// Returns: true

isNumber(NaN);
// Returns: true

// Number objects
isNumber(new Number(42));
// Returns: true

// Other types
isNumber('123');
// Returns: false

isNumber(true);
// Returns: false

isNumber(null);
// Returns: false

Parameters

• value (unknown): The value to check if it's a number.

Returns

(value is number): Returns true if the value is a number, otherwise false.