GVWR Calculator (payload left from GVWR, curb weight, passengers & cargo)

Understanding the GVWR payload calculator — concept and principle

This calculator checks whether a loaded vehicle stays within its gross vehicle weight rating (GVWR). From the GVWR and the curb weight it finds the payload capacity, then subtracts occupants, cargo and any trailer tongue weight to show how much payload is left. Use it before a road trip, a camping holiday or towing.

Payload left under the GVWR: with the default inputs the result is 150 kg left (75% of payload used).

How it is calculated

Payload capacity = GVWR − curb weight.
Planned load = occupants × average weight + cargo and accessories + trailer tongue weight.
Payload left = payload capacity − planned load (negative means over the rating).
Loaded vehicle weight = curb weight + planned load.
Share used = planned load ÷ payload capacity × 100; pounds = kg ÷ 0.45359237.

The principle

The GVWR is the maker's maximum for the vehicle and everything in it. The curb weight is the vehicle ready to drive with fluids but no people or cargo. The difference is what you may add. When towing, part of the trailer's weight rests on the hitch as tongue weight, and that counts against payload too. Brakes, tyres, suspension and handling are designed around these limits, so exceeding them makes stopping distances longer and can overload tyres.

Worked example

Default inputs: GVWR 2,500 kg, curb weight 1,900 kg, 4 occupants at 75 kg, cargo 150 kg, no tongue weight.

Payload capacity = 2,500 − 1,900 = 600 kg.
Planned load = 4 × 75 + 150 + 0 = 450 kg.
Payload left = 600 − 450 = 150 kg (331 lb).
Loaded weight = 1,900 + 450 = 2,350 kg; share used = 450 ÷ 600 = 75%.
Status = Within the GVWR.

Each point is the calculator re-run with only “Number of occupants including the driver” changed; the gold point is the default example. Change the inputs above and this chart follows your numbers.

Number of occupants including the driver	Payload left before reaching GVWR (kg)
1	375
2	300
3	225
4	150
5	75
6	0
8	-150

How to read the result

Staying within the GVWR is necessary but not enough. The tyre and loading placard on the door pillar gives a maximum combined weight of occupants and cargo, and each axle has its own rating (GAWR). A heavy load at the rear can exceed the rear axle rating even when the total is fine. Use real weights where you can: a public weighbridge gives the most reliable figure.

Common mistakes

Using the curb weight from a brochure for a different trim level.
Forgetting roof boxes, tow bars, and other fitted accessories.
Leaving out the trailer tongue weight.
Guessing occupant weights too low.

Keep in mind: Never exceed the GVWR, axle ratings or the tyre placard limit. If your vehicle is close to the limit, weigh it. Follow the owner's manual and local rules for loading and towing.

Frequently asked questions

How do I calculate payload?

Subtract the curb weight from the GVWR, then subtract everything you will carry.

Does trailer tongue weight count toward payload?

Yes. The weight on the hitch is carried by the vehicle and reduces the payload left.

What is the difference between GVWR and GAWR?

GVWR is the limit for the whole vehicle; GAWR is the limit for each axle.

Sources: NHTSA tire and loading information requirements, "Steps for Determining Correct Load Limit" as printed in US owner's manuals

Checked 9 Nov 2026. “Steps for Determining Correct Load Limit” as printed in US owner’s manuals under NHTSA’s tire and loading information requirements (combined occupant and cargo limit minus occupants = cargo capacity; trailer tongue load reduces it), checked in a current Kia owner’s manual; payload = GVWR − curb weight by definition of the ratings. Occupant weight is an example value.

Your numbers