Its in reg doc.(log book) as 'Mass in Service' this is the weight at which the car left the factory so they figure may be slightly different from 'Kerb weight' as stated in your car handbook which normally includes fuel.
There will be a higher figure. 'Max permissable mass' which is max allowed weight of car + load, ie max gross weight.
Thanks tents so it means the car is ok will be 86% with this figure but it has no handbook hence reason for asking and asking the dealer is like predicting the lottery numbers!!!