Math.trunc
Drops the fractional part of a number.
Available since: ES2015
Syntax
Math.trunc(x)Parameters
| Parameter | Type | Description |
|---|---|---|
| x | number | The number whose fractional part is dropped. |
Return value
numberThe integer part of the number.
Examples
The integer part:
console.log(Math.trunc(7.9));Output:
7The difference from Math.floor on negative numbers:
console.log(Math.trunc(-7.9));
console.log(Math.floor(-7.9));Output:
-7
-8Notes
Math.trunc() just cuts off everything after the point, while Math.floor() always rounds down. For positive numbers the result is the same.
See also
- Math.floor — Rounds a number down to an integer.
- Math.ceil — Rounds a number up to an integer.
- parseInt — Converts a string to an integer.
Related recipes
In the tutorial
- Numbers — Numbers in JavaScript — integers and fractions, rounding, the Math object, toFixed and the special values Infinity and NaN.