How to round a double to nearest Int in Swift

In this tutorial, we are going to learn about how to round a double to its nearest Int in Swift.

Using the round() method

We can round a double to the nearest Int by using the round() method in Swift.

Here is an example, that rounds the double 15.3 to the nearest integer 15.0:

import Foundation

var a = 15.3
a.round()
print(a)

Output:

15.0

If the decimal value is >=.5 then it rounds up to the nearest value. for example, it rounds the 15.7 to 16.0.

import Foundation

var b = 15.7
b.round()
print(b) // 16.0

The round() method modifies the original value assigned to the variable, if you want to preserve an original value then you can use the rounded() method.

Example:

import Foundation

var b = 15.7
var c = b.rounded()

print(b) // 15.7
print(c) // 16.0