The Number.isInteger() method returns true if a value is an integer of the datatype Number. Otherwise it returns false.

Feb 1, 2013 · You need to check both if the type of the variable is a number, and to check for integer I would use modulus. alert(typeof data === 'number' && data%1 == 0);

Mar 5, 2025 · The Number.isInteger() static method determines whether the passed value is an integer. Try it function fits(x, y) { if (Number.isInteger(y / x)) { return "Fits!"; } return "Does NOT fit!"; } console.log(fits(5, 10)); // Expected output: "Fits!"

Jun 6, 2024 · To check if a value is a number in JavaScript, use the typeof operator to ensure the value's type is 'number'. Additionally, functions like Number.isFinite() and !isNaN() can verify if a value is a valid, finite number.

The fastest possible way to check if something is a number is the "equal to self" check: var n = 'a'; if (+n === +n) { // is number } It is ~3994% faster than isNaN in the latest version of Chrome. See the performance test here: jsperf.com/isnan-vs-typeof/5 –

Aug 7, 2013 · There is a javascript function called isNaN (val) which returns true if val is not a number. If you want to use val as a number, you need to cast using parseInt () or parseFloat () EDIT: oops. Corrected the error as mentioned in the comment.

Jan 10, 2025 · The Number.isInteger() method in JavaScript is useful for checking whether a number is a whole number or not. Syntax: Number.isInteger(value); Parameters: value: The value to be checked. Return Value: It returns a boolean value,i.e. either true or false. It will return true if the passed value is of the type Number and an integer, it returns false.

Oct 4, 2023 · In this article, we will see how to check whether a number is a float or an integer in JavaScript. A float is a number with a decimal point, while an integer is a whole number or a natural number without having a decimal point.

May 18, 2024 · In this tutorial, we'll explore three different ways to check if a value is a number in JavaScript, using the isInteger(), typeof(), and isNaN() methods. The isInteger() method in JavaScript accepts a single parameter, the value being tested. The method returns true if the value is numeric, and false if it isn't:

The parseInt() method returns the integer part from the string or float number. We will also parse the integer part from the number and compare it with our real number. If the returned value from the parseInt() method and actual number values is the same, then the number is an Integer.