Due to a quirk of unifying 2 standards, Europe and the UK, the range is 216.2 volts to 253.0 volts.
That encompasses infrastructure built to a tighter tolerance around 220V in Europe and infrastructure built to a tighter tolerance around 240V in the UK (and Australia).
We expect 3150W out of a kettle most of the time. Our heaters will say 3kW.
Usually you’ll find a few volts over 240 out of our outlets and that’s to design spec.
Sure and cops can’t lie about being a cop.
Definitely real rules.