Hi Ed,

It depends on the year and the specification of your i30, but assuming it’s the second generation model (2012 to 2017) then look at the steering wheel - there should be a button on it that looks like a page symbol. Push that, and in the display between the main dials there should be a list of options. Scroll through until you find an option for Display or Units and that should allow you to change from imperial to metric. Have a look at your owner's manual if you need any help.