Free Payload Capacity calculator with clear step-by-step results.
Payload is gross vehicle mass minus kerb mass, but that headline figure has to fund occupants, fitted accessories and - critically - the downward load a trailer puts on the towball, which counts against the tow vehicle rather than the trailer. What remains is the real cargo allowance.
Gross payload
Payload = gross vehicle mass rating - kerb mass
Available cargo
Available = gross payload - occupants - accessories - towball download
Exceeding gross vehicle mass, axle limits or towing ratings is illegal and dangerous, and can invalidate insurance. Verify against the manufacturer's plate and have the loaded vehicle weighed.
Yes. The vertical load the coupling applies is carried by the vehicle's suspension and counts toward gross vehicle mass, which is how many loaded tow vehicles end up illegally overweight.
Often optimistically so. Brochure kerb mass may exclude a full fuel tank, spare wheel or optional equipment. Weighing the vehicle is the only reliable method.