Payload Calculation
Example of Tire and Loading Information Label:

Payload is the total weight of cargo and passengers that your vehicle carries. The maximum payload for your vehicle is shown on the Tire and Loading Information label. The label is located either on the center pillar or on the edge of the driver's door. Vehicles exported outside the USA and Canada may not have a tire and loading label. Look for the statement "The combined weight of occupants and cargo should never exceed XXX kg or XXX lbs" for the maximum payload. The payload shown on the Tire and Loading Information label is the maximum payload for your vehicle as built at the assembly plant. If you install any additional equipment on your vehicle, you must determine the new payload. Subtract the weight of the added equipment from the payload listed on the Tire and Loading Information label. When towing, the trailer tongue weight or kingpin weight is also part of the payload.
Test yourself
A quick Ford Escape quiz: every answer comes with an explanation and a link to the manual page.