Get a random truthy/falsy value

fiftyFifty.js

/**
 * Get a random truthy/falsy value
 * {@link https://gist.github.com/kieranbarker/25b1b4b4cef14c65b10dcefdc462f6ee}
 * @returns {Number} 1 (truthy) or 0 (falsy)
 */
function fiftyFifty () {
  return Math.round(Math.random());
}

MIT License

Copyright (c) 2021 Kieran Barker

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

It's not necessary, but if you really wanted to return an explicit boolean value for some reason, you could force the conversion using a double NOT (!) operator:

/**
 * Get a random boolean value
 * {@link https://gist.github.com/kieranbarker/25b1b4b4cef14c65b10dcefdc462f6ee}
 * @returns {Boolean} True or false
 */
function fiftyFifty () {
  return !!Math.round(Math.random());
}

Read the blog post:

https://kbarker.dev/blog/get-a-random-truthy-falsy-value-in-javascript/