How to Remove the Decimal Part of a Number in JavaScript ?

The decimal portion of a number in JavaScript can be removed through various methods, including the Math. trunc( ) method, Math. floor( ) method, Math. ceil( ) method, and Math. round( ) method.

Syntax

Math.trunc(11.5) //  Output: 11
Math.floor(12.5) // Output: 12
Math.ceil(15.5)  // Output: 15
Math.round(-20.5) // Output: -20

Using Math.trunc() Method

The Javascript  Math. trunc() method is used to return the integer part of a floating-point number by removing the fractional digits.

Example: The below code illustrates how to remove the decimal part of a number Using the Math. trunc( ) Method.

Javascript

console.log(Math.trunc(15.80));
console.log(Math.trunc(0.12));
console.log(Math.trunc(-10.80));

Output:

15
0
-10

Using Math.floor() Method

Math.floor() method is used to round off the number to its nearest integer and returns the smallest integer greater than or equal to the given number. 

Example: The below code illustrates how to remove the decimal part of a number Using Math.floor() Method.

Javascript

console.log(Math.floor(-12.10));
console.log(Math.floor(0.79));

Output:

-13
0

Using Math.ceil() Method

Math.ceil() method is used to return the smallest integer greater than or equal to a given number.

Example: The below code illustrates how to remove the decimal part of a number Using Math.ceil() Method.

Javascript

console.log(Math.ceil(32.80));
console.log(Math.ceil(0.80));
console.log(Math.ceil(-29.70));

Output:

33
1
-29

Using Math.round() Method

Math.round() method is used to round a number to its nearest integer. If the fractional part of the number is greater than or equal to .5, the argument is rounded to the next higher integer. 

Example: The below code illustrates how to remove the decimal part of a number.

Javascript

console.log(Math.round(42.80));
console.log(Math.round(0.80));
console.log(Math.round(-89.70));

Output:

43
1
-90