There are a number of things to consider when working out your vehicle's load rating.

Firstly, different vehicles have different roof ratings. You need to know the load rating of your vehicle. This information will be easy to find in your vehicle's owners manual.

Secondly this calculator assumes the condition of your vehicle roof/gutter is at its best.

It is important to remember, if you buy an accessory or holder and attach it to your rack or tray, you must also include the weight of these in your cargo allowance.

Also not every product can be safely load the same, some bars might not support as much weight for example.

It is very unsafe to overload your vehicle. The "she'll be right" approach is not appropriate in this context, and failure to follow the load ratings in each circumstance could result in damage to your vehicle, potential loss of your load, voiding warranty or insurance or cause traffic accidents. It's illegal to overload your vehicle.

This estimate is an aid only. Always use the lowest load rating specified by the vehicle manufacturer, rack system, accessories and installation instructions. Include the weight of all racks, brackets, holders and accessories. Do not exceed the vehicle's roof, GVM or axle limits. Check load restraints regularly, particularly during off-road use.