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# Convert negative number to positive in JavaScript

April 26, 2021  ‐ 1 min read

Sometimes you may need to turn a negative number into a positive one. Of course there is the high(or elementary?) school mathematics approach: multiplying two negative numbers gives a positive.

``````let x = -5;
x *= -1;
console.log(x); // => 5
``````

But this only guarantees a positive number if you are sure that your variable is negative. Otherwise you will a negative and positive number which gives a negative obviously.

In that case you may use the `Math.abs()` function that comes with JavaScript to convert negative number to positive. The `Math.abs()` function returns the absolute value of the number you pass it as a parameter.

If you pass a negative number to `Math.abs()` it returns the negation of that number. When you pass it a positive number it returns the number as is, and the same goes for when you pass the number zero.

``````Math.abs(-5); // => 5
Math.abs(5); // => 5
Math.abs(0); // => 0
``````

By using `Math.abs()` you are ensured to have a positive number returned to you.