Are they all checked?

Simplest way to check whether all checkbox input fields checked or not; by converting a NodeList to an Array using ES6 ... spread operator so we can attach every() method to it;

Checkout the Are they all checked? Demo on jsfiddle

[...document.querySelectorAll('input')].every(checkbox => checkbox.checked)

What would be the benefit for using a spread operator instead of Array.from()?

Thanks Arden! You can definitely do the same thing with Array.from, but in my case, the ... is better use IMO. Less code, easy to remember, plus performance. Cheers

Ah btw, I didn't knew Array.from took in two arguments, so an alternative could be

Array.from(document.querySelectorAll('input'), checkbox => checkbox.checked);

Correct me if I'm wrong.

I kinda like Array.from() because it's so verbose and easy readable, but I guess that's also because not everyone (read: me) is used to spread operators yet. Thanks for the clarification!

Also

Array.prototype.every.call(document.querySelectorAll('input'), checkbox => checkbox.checked)