JavaScript Number.isInteger()

The JavaScript Number.isInteger() method determines whether the passed value is an integer.

The syntax of the isInteger() method is:

Number.isInteger(value)

The isInteger() method is called using the Number class name.


Number.isInteger() Parameters

The isInteger() method takes in:

  • value - The value to be tested for being an integer.

Return value from Number.isInteger()

  • Returns a Boolean representing whether the given value is an integer.

Note: The isInteger() method returns false for NaN and Infinity.


Example: Using Number isInteger()

console.log(Number.isInteger(453)); // true
console.log(Number.isInteger(-44)); // true
console.log(Number.isInteger(5.0)); // true

console.log(Number.isInteger(456.129)); // false
console.log(Number.isInteger(Math.PI)); // false

console.log(Number.isInteger(NaN)); // false
console.log(Number.isInteger(Infinity)); // false
console.log(Number.isInteger("10")); // false

console.log(Number.isInteger(true)); // false
console.log(Number.isInteger(false)); // false
console.log(Number.isInteger([1])); // false

Output

true
true
true
false
false
false
false
false
false
false
false