I got a pedal custom made in the US and just realised (now it's been posted) that I may not be able to power it with my standard UK power supply.

What do I need to power it in the UK?
as long as it still takes 9v you're all good

the difference would be that (being in North America), I'd power a pedal with my 115VAC to 9vDC adapter, while you would power the same pedal with a 230VAC to 9vDC adapter. either way the pedal still only gets 9v
Oh okay awesome.

So it's the power it takes from the mains thats the difference? And not the output?