The gross vehicle weight rating is determined by the manufacturer and is indicated on the vehicle compliance label.
For your vehicle
The compliance label is a plate or sticker that lists technical information, including the name of the manufacturer, year of manufacture, vehicle identification number and GVWR.
For heavy vehicles, the compliance label is usually affixed to the driver's door frame or the driver's door. It may also be located on the left side of the dashboard.
If your vehicle does not have a compliance label, contact your dealership or the vehicle's manufacturer to obtain the GVWR.
For your trailer
The compliance label for a trailer or semi-trailer is usually located on the front left side, facing out so it is clearly visible at all times.
A trailer is a road vehicle designed for being drawn by another vehicle and it may or may not stand horizontally on its own.
A semi-trailer is a road vehicle the front of which rests on the fifth wheel of the vehicle pulling it.
There is no compliance label for hand crafted trailers. In that case only, you may calculate the GVWR as follows:
Note: to convert pounds (lbs) to kilograms (kg), divide by 2.2046 (1 kg = 2.2046 lbs).
Weight in kg = Weight in lbs / 2.2046
The gross vehicle weight rating can also be confirmed in an engineer's report..