500ml to 440ml?
Edit: the 440 on the right, is the last of a can that I bought in a four pack. The 500 on the left, is one of three I bought as singles.
Packaged Guinness comes in 440 milliliters. Single cans of Guinness come in 500 mL.
Apparently, that’s how Guinness does it here in Canada.
And apparently, I lazily avoided any attempt to research or apply any level of critical thinking before posting.
The UK measures alcohol in units to track total amount consumption, as it’s not easy to track with percentage in volume. A unit is 10 ml of pure alcohol, and cans/bottles/etc have the total units printed. That way it’s supposed to be easier to track how much alcohol you drink e.g. if you drink a beer, then a wine - now that’s 4 units.
I’m not British so I’m not used to units, but at least that’s the theory.