If you mean the values seen in the top left corner of the map editor, these show the relative coordinates of visible, local map (from 0, 0, Z-level to 131, 131, Z-level).
If you want the absolute coordinates, you’re probably better off with Debug Menu → [i]nfo... → Check [g]ame state (third or forth screen).
If you need help with reading the coordinates of the different map types (overmap, local, etc.), there is a really, really lenghty explanation I’ve come up with.