Towing capacity calculator
Type in the ratings from your vehicle's owner's manual or door sticker and the weight of your loaded trailer. The calculator shows your margin against the towing rating, the share of it you use, a tongue weight estimate and, if you enter it, whether the combined weight stays within the GCWR. It never looks up or states what a vehicle can tow; the figures in the form are placeholders to replace.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Choose pounds or kilograms.
- Enter the towing capacity from your manual, then the weight of your trailer as loaded.
- Enter the weight of the tow vehicle with passengers and cargo, and the GCWR if your manual gives one.
- Adjust the tongue weight share if you know it.
How it works
- Margin = rated towing capacity − trailer weight; share used = trailer ÷ rated.
- Tongue weight = trailer weight × share. The 10% and 15% lines show the usual rule-of-thumb range.
- Combined weight = vehicle + trailer, compared with the GCWR.
Worked example
Rating 5,000 lb and a 3,800 lb trailer: margin 1,200 lb, 76% used. Tongue weight at 12% is 456 lb (380 to 570 lb for 10% to 15%). With a loaded vehicle of 5,200 lb the combined weight is 9,000 lb, which is 2,000 lb under an 11,000 lb GCWR. These figures are examples only.
Tips
- Weigh the loaded trailer at a public scale rather than guessing.
- Tongue weight takes up payload in the tow vehicle.
- Leave margin: towing near a limit makes hills and braking harder.
Frequently asked questions
Where do I find my vehicle's towing capacity and GCWR?
In the owner's manual, often in a towing section, and on the manufacturer's information for your exact model, engine and equipment. Some vehicles also show weight ratings on a door-jamb label. This calculator does not supply them; the numbers in the form are placeholders.
What is tongue weight?
The downward force the trailer coupling puts on the tow vehicle. A common rule of thumb is about 10% to 15% of the loaded trailer weight; too little can make a trailer sway, too much overloads the rear axle. It is a guideline, not a rating, and your manuals may give limits that differ.
What is GCWR?
The gross combined weight rating is the maximum allowed weight of the loaded tow vehicle and the loaded trailer together. The tool compares your vehicle plus trailer weight with it when you enter a value above zero.
Is a trailer under the rating always safe to tow?
Not necessarily. Other limits can apply, such as payload, hitch rating, axle ratings and tyre ratings. Tongue weight also counts as load on your vehicle. Check each limit in your manuals and weigh a loaded rig if in doubt.