# JS generate random boolean

Simple question, but I'm interested in the nuances here.

I'm generating random booleans using the following method I came up with myself:

```
const rand = Boolean(Math.round(Math.random()));
```

Whenever `random()`

shows up, it seems there's always a pitfall - it's not truly random, it's compromised by something or other, etc. So, I'd like to know:

a) Is the above the best-practice way to do it?

b) Am I overthinking things?

c) Am I underthinking things?

d) Is there a better/faster/elegant-er way I don't know of?

(Also somewhat interested if B and C are mutually exclusive.)

*Update*

If it makes a difference, I'm using this for movement of an AI character.

## Answers:

Technically, the code looks fine, but just a bit too complex.
You can compare `Math.random()`

to `0.5`

directly, as the range of `Math.random()`

is `[0, 1)`

(this means 'in the range 0 to 1 including 0, but not 1'). You can divide the range into `[0, 0.5)`

and `[0.5, 1)`

.

```
var random_boolean = Math.random() >= 0.5;
```

```
// Example
console.log(Math.random() >= 0.1) // %90 probability of get "true"
console.log(Math.random() >= 0.4) // %60 probability of get "true"
console.log(Math.random() >= 0.5) // %50 probability of get "true"
console.log(Math.random() >= 0.8) // %20 probability of get "true"
console.log(Math.random() >= 0.9) // %10 probability of get "true"
```