Trailer Tongue Weight Calculator
Correct tongue weight is one of the most important safety numbers in towing. Too little tongue weight invites trailer sway; too much overloads the rear axle and unloads the steering axle. This calculator works two ways: enter a measured tongue weight to see its percentage of the loaded trailer weight, and set your target percentage range to see the tongue weight band you should aim for. Always cross-check the result against the towing ratings stamped on your hitch, ball, and vehicle.
Tongue weight formula
Tongue weight percent = (tongue weight / gross trailer weight) * 100
Target low (lb) = gross trailer weight * (min percent / 100)
Target high (lb) = gross trailer weight * (max percent / 100)
The default 10% to 15% band is a common guideline for conventional ball hitches. Your hitch, ball, and vehicle ratings always take priority over any percentage rule.
Worked example
A loaded trailer weighing 5,000 lb with a measured tongue weight of 600 lb has a tongue weight of (600 / 5,000) * 100 = 12.00%, which sits inside the 10% to 15% band. The target band is 500.00 lb to 750.00 lb, so 600 lb is comfortably within range.
Trailer tongue weight: frequently asked questions
What is trailer tongue weight?
Tongue weight is the downward force the trailer coupler exerts on the tow vehicle's hitch ball. It is part of the loaded trailer's total weight, transferred to the hitch because some of the load sits ahead of the trailer axle. Correct tongue weight keeps the trailer stable; too little causes dangerous sway, and too much can overload the rear axle and lighten the steering axle.
What tongue weight percentage is recommended?
A widely used guideline for conventional ball-hitch trailers is a tongue weight of 10% to 15% of the total loaded trailer weight. The exact safe range depends on your vehicle and hitch ratings, which are set by the manufacturer, so this calculator lets you set the target percentages and always compare against your equipment's stamped limits.
How do I reduce trailer sway?
Sway often comes from too little tongue weight, meaning too much of the load sits behind the trailer axle. Moving cargo forward of the axle raises tongue weight and improves stability. Never exceed the hitch, ball, or vehicle ratings while doing so, and load heavy items low and centred over or just ahead of the axle.
Sources
- U.S. National Highway Traffic Safety Administration: Towing a Trailer, on safe loading and weight distribution.
Reviewed by the CalculatorHub team, edited by James Graham, 19 June 2026. See our methodology.