What metric unit is used to measure distance?
The meter is the standard measure of distance in metric units.
Depending on the area of study, prefixes will be added to make the magnitude more relevant to the subject. For example, some unit conventions will use IPS (inch pound second), or MKS (meter kilogram second), indicating that the measurements will be in this convention, simply for the sake of making the magnitude more reasonable to the application.
Depends on the distance you mean
Between cities kilometres
Between pubs metres
Length of a pencil centimetres
Length of a bug millimetres