Calculators · Towing and loads

Towing, payload and tongue weight calculator

A vehicle has several weight limits, and towing safely means staying inside all of them at once: its gross vehicle weight rating (GVWR), its gross combined weight rating (GCWR) and its towing capacity. The trailer’s tongue weight counts against the tow vehicle’s payload too. These calculators work out your remaining payload, a sensible tongue weight and whether the whole combination stays within its rating. The official ratings on your vehicle’s door label and in its handbook always take priority over any calculation.

Payload capacity and what is left

Payload capacity is the GVWR minus the vehicle’s actual empty weight. Everything you add — passengers, luggage, accessories and a trailer’s tongue weight — comes out of it. Weigh the vehicle if you can; brochure kerb weights often omit options.

Results
Payload capacity—GVWR minus kerb weight.
Payload remaining—Negative means the vehicle is overloaded.
Status—Whether the loaded vehicle is within its GVWR.

Formula
payload capacity = GVWR − kerb weight
remaining = capacity − passengers − cargo

Trailer tongue weight

For a conventional ball-hitch trailer, tongue (nose) weight of about 10–15% of the loaded trailer weight keeps it stable. Too little can cause dangerous sway; too much overloads the tow vehicle’s rear axle. Many European car makers specify a lower fixed maximum, often 75–150 kg — check yours.

Results
Tongue weight—Downward load on the hitch at the chosen percentage.
At 10%—Lower end of the usual range.
At 15%—Upper end of the usual range.

Formula
tongue weight = trailer weight × percentage

Combined weight against GCWR

The gross combined weight rating is the most the loaded tow vehicle and loaded trailer may weigh together. This checks the combination against it; the trailer must also stay within the vehicle’s own towing capacity.

Results
Combined weight—Loaded vehicle plus loaded trailer.
Margin to GCWR—Negative means the combination is over its rating.
Status—Checks both the GCWR and the towing capacity.

Formula
combined = vehicle + trailer
margin = GCWR − combined

Worked example: a pickup towing a caravan

  1. GVWR 3,200 kg minus a 2,300 kg kerb weight leaves 900 kg of payload.
  2. A 2,000 kg caravan at 12% puts 240 kg on the hitch.
  3. With 300 kg of people and 240 kg of tongue weight, 360 kg of payload remains for luggage.
  4. Loaded vehicle 3,000 kg plus 2,500 kg trailer is 5,500 kg — 500 kg inside a 6,000 kg GCWR.

Common weight terms

TermMeaning
Kerb weightEmpty vehicle with fluids and a full tank, without occupants or load
PayloadEverything the vehicle may carry: GVWR minus kerb weight
GVWR / GVMMaximum permitted weight of the loaded vehicle
GCWR / GCMMaximum permitted weight of the loaded vehicle and trailer together
Tongue (nose) weightDownward load of the trailer on the hitch
Gross axle weight ratingMaximum load permitted on each axle

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About these results

Results are theoretical estimates from standard engineering formulas. Real-world figures depend on conditions these formulas do not capture. Always follow the manufacturer's specifications for maintenance, loading and safety decisions.

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