Towing Capacity Calculator
Enter your vehicle's rated capacity and what you're actually loading — results update as you type, and the link in your address bar always reflects your numbers.
How this calculator works
Your vehicle's rated max towing capacity has to cover everything it's carrying at once, not just the trailer on the hitch — so this tool adds the trailer/load weight to the passengers and cargo already inside the vehicle to get the total weight pressing against that rating. Subtracting that total from the rated capacity gives your remaining margin: positive means you're within the manufacturer's rating, negative means you're over it. Separately, it recommends a tongue weight — the downward force the trailer puts on the hitch — as 10% to 15% of the trailer's own weight, a standard, commonly-cited trailer-safety guideline that helps avoid both sway (too little tongue weight) and an overloaded hitch (too much).
Worked example
With the defaults — a 7,000 lb rated capacity, a 5,000 lb trailer, and 400 lb of passengers and cargo already in the vehicle — total weight against the rating is 5,000 + 400 = 5,400 lbs, leaving a remaining margin of 7,000 − 5,400 = 1,600 lbs (safely under the limit). Recommended tongue weight is 10–15% of the 5,000 lb trailer: 500 to 750 lbs. Now try a 7,500 lb trailer with the same 7,000 lb capacity and 400 lb occupant/cargo load: total weight is 7,900 lbs against a 7,000 lb rating, so the margin becomes −900 lbs — the tool clearly labels that as over the limit, exactly the situation it's built to catch before you hook up.
Frequently asked questions
Where do I find my vehicle's real towing capacity?
In the owner's manual or on the driver-door-jamb sticker (open the driver's door and look at the pillar) — not the number often quoted in ads or on a manufacturer's spec sheet. Advertised max-tow figures are frequently measured on a stripped-down, two-wheel-drive configuration with no options and a single occupant; your actual vehicle, with its specific engine, drivetrain, and options, can be rated meaningfully lower. Always confirm against your own vehicle's documentation before you rely on a number.
Why does tongue weight matter?
Tongue weight is how much of the trailer's weight presses down on your hitch. Too little (well under 10% of trailer weight) and the trailer can start to sway at speed, sometimes dangerously. Too much (well over 15%) overloads the hitch and rear axle, pushing down the back of the vehicle and lightening the front, which hurts steering and braking. The commonly-cited 10–15% range balances both failure modes.
Does this include the weight of a full fuel tank and passengers?
Only if you put it in the "occupants + cargo already in the vehicle" field. That field should include everyone riding along, everything in the trunk or bed, and a full tank of gas if that's realistic for the trip — not just the empty trailer's weight. Underestimating this number is one of the most common ways people accidentally end up over their real towing limit.
Is being "under the limit" on this calculator always safe?
No. A positive remaining margin here only checks one number — trailer plus occupant/cargo weight against your rated max towing capacity. It doesn't check your hitch class rating, your tires' load rating, or whether your vehicle has (or needs) trailer brakes for that weight. Treat this as a planning aid, not a full safety certification — verify the other specs separately before you tow.