The height if a character, or any other selected item, is shown in Info at the top left of the stage.
It can be turned on and off by using the Ctrl+F keys, or checking the box in the Preferences panel. The units can be set to either CM or FT, depending on what you require.
The height can be adjusted using the Height Morph slider and changes are shown in real time in the Info section.
System: Win 10 Pro (1903), Asus X99-E WS, CPU i7-5930K -3,5 GHz, 32 GB DDR4 2666-16 RAM, NVidia GTX 1080 Ti GPU - 11 GB VRAM(Driver Studio-441.28), Samsung 850 Pro 512 GB SSD, 6 TB HD storage.