Payload is the one number pickup and SUV owners are most likely to be wrong about, because the figure people remember is the towing capacity from an advertisement and the figure that actually constrains them is written on a sticker inside the driver's door. This GVWR payload calculator works from that sticker. You supply the ratings for your own vehicle, it subtracts what you are carrying, and it reports what is left and which rating runs out first.
Arb Digital publishes it as part of a free tools library, and it deliberately contains no table of vehicle weights. Ratings vary between trim levels, cab configurations, axle ratios and even individual builds of the same model, so a generic figure looked up online is not your vehicle's figure. Every input here comes from your placard, your hitch, your tyres or a weighbridge.
What This GVWR Payload Calculator Does
Payload capacity is gross vehicle weight rating minus curb weight — that is, everything the vehicle is rated to carry beyond itself. The calculator subtracts occupants, cargo and permanently fitted accessories from that capacity, then subtracts trailer tongue weight, because tongue weight sits on the tow vehicle and consumes payload exactly as a passenger does. What remains is your true spare capacity.
It then works backwards to find the heaviest trailer the entered ratings permit, testing five separate constraints: remaining payload against tongue weight, combined tyre load rating, gross combined weight rating, the hitch's weight rating and the hitch's tongue rating. The lowest of those governs, and the result names it. If you are not towing, set the trailer weight to zero and read the payload figures on their own.
How to Use It
- Read the door placard. The Tire and Loading Information label carries the vehicle capacity weight and tyre sizes; the certification label carries GVWR and the front and rear axle ratings.
- Get a real curb weight. Brochure curb weights describe a base model with no options. If your vehicle has a canopy, a heavy bumper or a long-bed configuration, weigh it.
- Count everybody and everything. Passengers, dogs, tools, fuel in auxiliary tanks, water in a tank, and anything bolted on after the vehicle left the factory.
- Enter the trailer figures. Loaded trailer weight, and the tongue weight percentage your trailer manufacturer states for the way it is loaded.
- Read which limit governs. That is the number that matters. Increasing anything else will not raise it.
The Formula / How It's Calculated
Payload capacity = GVWR − curb weight. Tongue weight = loaded trailer weight × tongue percentage. Payload used = occupants + cargo + accessories + tongue weight. Payload remaining = payload capacity − payload used. Loaded vehicle weight = curb weight + payload used.
The maximum trailer weight is the smallest of: (payload capacity − occupants − cargo − accessories) ÷ tongue fraction; (tyre rating − loaded vehicle weight excluding tongue) ÷ tongue fraction; GCWR − loaded vehicle weight excluding tongue; the hitch weight rating; and the hitch tongue rating ÷ tongue fraction.
Worked example, which is what the page loads with. GVWR 7,000 lb and curb weight 5,400 lb give a payload capacity of 1,600 lb. Occupants 350, cargo 400 and accessories 150 total 900 lb, leaving 700 lb before the trailer is attached. At a 12% tongue weight, a 5,000 lb trailer puts 600 lb on the hitch, so payload used is 1,500 lb and payload remaining is 100 lb. Working backwards, the payload limit allows 700 ÷ 0.12 = 5,833 lb of trailer, the tyre rating allows the same 5,833 lb, GCWR allows 7,700 lb, the hitch weight rating allows 7,500 lb and the hitch tongue rating allows 750 ÷ 0.12 = 6,250 lb. The lowest figure governs, so the answer is 5,833 lb, limited by payload — not by the 14,000 lb combined rating that sounds so generous.
Why Payload Runs Out Before Towing Capacity
Advertised towing capacity is calculated for a vehicle carrying a single 150 lb driver and nothing else. Add a family, a full tank, a toolbox and a canopy and several hundred pounds of payload have gone before the trailer is connected. Since tongue weight is typically 10 to 15% of the trailer for a conventional hitch, every 1,000 lb of trailer takes another 100 to 150 lb of payload with it. Half-ton trucks routinely hit their payload ceiling long before they approach the tow rating on the tailgate sticker.
This is not a technicality. Exceeding GVWR loads the springs, brakes and tyres beyond what they were designed and tested for, lengthens stopping distances, and in many jurisdictions is an offence with insurance consequences. It is also the mechanism behind a large share of tyre failures on loaded vehicles.
The Ratings and Which One Wins
GVWR caps the whole vehicle including everything in and on it. GAWR caps each axle separately, and it is possible to be under GVWR while overloading the rear axle — which is exactly what a heavy tongue weight or a load carried behind the rear wheels does. The tyre load rating caps what the tyres can carry at the placard pressure, and fitting tyres with a higher rating does not raise GVWR, because GVWR is a whole-vehicle rating covering brakes, suspension and frame as well.
The hitch carries two separate numbers stamped on the receiver: a maximum trailer weight and a maximum tongue weight, often with different figures for weight-carrying and weight-distributing setups. And the GCWR caps the tow vehicle and trailer added together. The federal placard requirement itself is set out in 49 CFR 571.110, which specifies the "Tire and Loading Information" label and the combined occupant and cargo weight it must state.
Tongue Weight Is Not Optional Arithmetic
Tongue weight is the vertical download the coupler puts on the hitch ball, and it is the single most misunderstood figure in towing. Too little and the trailer sways, because the centre of mass sits too far back; too much and the tow vehicle's front axle unloads, which degrades steering and braking. The conventional working range is 10 to 15% of loaded trailer weight for a bumper-pull trailer and higher for a fifth wheel or gooseneck, but the trailer manufacturer's specification governs, and the only way to know the real figure is to weigh the tongue.
The percentage also changes when you move the load. Shifting cargo forward of the trailer axles raises tongue weight; shifting it rearward lowers it. That means the same trailer can be legal and stable one day and neither the next, with no change in total weight. Weight-distributing hitches redistribute some of the tongue load back to the trailer and front axles but do not reduce it, and they do not raise any rating.
Weighing Beats Calculating
Everything on this page is arithmetic on numbers you supplied. It cannot see load distribution, it does not know whether your rear axle is over its rating while the vehicle as a whole is under GVWR, and it assumes your curb weight input is accurate. A public weighbridge will give you axle-by-axle figures for the loaded combination in a few minutes, and those figures are the ones that count.
Tyre condition matters just as much as the numbers. Load ratings assume the placard inflation pressure, and an underinflated tyre carrying a rated load runs hot, which is the classic failure sequence on a loaded trailer in summer. NHTSA's TireWise tire safety information covers load rating, pressure and ageing. The dimensional weight calculator and the freight class calculator handle the shipping side of load arithmetic, and the weight converter covers pounds to kilograms if your placard is metric.
Arb Digital maintains a large free tools library covering logistics, measurement and everyday arithmetic, and our team is happy to point you at the right one.
Browse Free Tools Talk to Arb DigitalCommon Mistakes to Avoid
- Using a brochure curb weight — published figures describe a base configuration, and options, accessories and fuel all add weight your vehicle actually carries.
- Forgetting that tongue weight is payload — it sits on the tow vehicle and consumes capacity exactly as passengers and cargo do.
- Assuming bigger tyres raise the limit — GVWR covers brakes, frame and suspension as well, and fitting higher-rated tyres does not change it.
- Checking GVWR but not the axle ratings — a rear axle can be over its GAWR while the vehicle as a whole is comfortably under GVWR.
- Trusting an advertised tow rating — it is calculated for a vehicle carrying a driver and nothing else, which is not the vehicle you are driving.
Related Free Tools From Arb Digital
Use the weight converter for pounds and kilograms, the dimensional weight calculator when a carrier charges on volume rather than mass, the freight class calculator for commercial shipments, the fuel cost calculator to see what towing does to a trip budget, and the pallet calculator for loading arithmetic. Everything else is in the tools hub.
Frequently Asked Questions
GVWR and the front and rear axle ratings are on the certification label inside the driver's door frame, and the Tire and Loading Information placard states the combined occupant and cargo weight. Curb weight is best measured on a weighbridge, because published figures describe a base configuration rather than your actual vehicle.
Yes. Tongue weight presses down on the hitch, which is part of the tow vehicle, so it consumes payload capacity in exactly the same way a passenger does. At a 12% tongue weight, a 5,000 lb trailer uses 600 lb of payload before anyone gets in the vehicle.
The lowest one. GVWR, each axle's GAWR, the combined tyre load rating, the hitch weight rating and the hitch tongue rating are separate limits, and being within four of them means nothing if you exceed the fifth. The calculator reports which limit runs out first.
No. Airbags, helper springs and higher-rated tyres can change how a vehicle sits and rides, but GVWR is a manufacturer rating covering the brakes, frame, suspension and axles as a system. Modifying components does not raise the rating on the placard.
Because advertised tow ratings assume a vehicle carrying a single driver and no cargo. Every passenger, accessory and pound of gear reduces the payload available for tongue weight, and payload usually runs out long before the combined weight rating does.
Use the figure your trailer manufacturer specifies for the way the trailer is loaded, and confirm it by weighing the tongue. A conventional bumper-pull trailer is commonly in the 10 to 15% range and a fifth wheel or gooseneck is considerably higher, but moving cargo within the trailer changes it.
No. It performs arithmetic on the figures you enter and cannot see your vehicle, your load distribution, your tyre condition or the rules in your jurisdiction. Weigh the loaded combination axle by axle at a public weighbridge and check your local regulations before relying on any figure.
This tool performs weight arithmetic only, using ratings you supply. It is not a legal or engineering assessment, it cannot verify any figure you enter, and it does not account for load distribution, axle-by-axle loading, tyre condition, road conditions or the towing rules that apply where you drive. Overloading a vehicle affects braking and handling and can cause tyre failure. Always work from your own vehicle's placard and manufacturer documentation, weigh the loaded combination, and consult a qualified professional where anything is unclear.
