question on weight

need some help working out weight of a gantry to convert it to kgf-cm or kgf-m to N m.
the gantry weight is about 200 kg.
do i just do 200kg-m to Nm or is it 200kg-cm to Nm.
i know how to convert one to the other im not sure if i use 200kg-cm or 200kg-m to work out the conversion from 200kg to Nm