# random(using:) Returns a random Boolean value, using the given generator as a source for randomness. ``` static func random(using generator: inout T) -> Bool where T : RandomNumberGenerator ``` ## Parameters `generator` The random number generator to use when creating the new random value. ## Return Value Either `true` or `false`, randomly chosen with equal probability. ## Discussion This method returns `true` and `false` with equal probability. Use this method to generate a random Boolean value when you are using a custom random number generator. ``` let flippedHeads = Bool.random(using: &myGenerator) if flippedHeads { print("Heads, you win!") } else { print("Maybe another try?") } ``` > Note: The algorithm used to create random values may change in a future > version of Swift. If you’re passing a generator that results in the > same sequence of Boolean values each time you run your program, that > sequence may change when your program is compiled using a different > version of Swift. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)