Trailer Tongue Weight Calculator
Calculate safe trailer tongue weight for towing.
Find the ideal tongue weight percentage (10–15%) and check if your hitch and vehicle can handle the load.
Tongue weight is the downward force that the trailer’s front coupler exerts on the tow vehicle’s hitch ball. Getting this right is critical for safe towing.
The general rule: tongue weight should be 10–15% of the total loaded trailer weight (Gross Trailer Weight, or GTW).
Example: If your loaded trailer weighs 3,000 kg (6,600 lb), the tongue weight should be 300–450 kg (660–990 lb).
Why does tongue weight matter?
Too little tongue weight (under 10%): The trailer tends to sway and fishtail. This is the most dangerous scenario, especially at highway speeds. Trailer sway is the leading cause of towing accidents.
Too much tongue weight (over 15%): The front of the tow vehicle lifts, reducing steering and braking effectiveness. Rear tyres are overloaded. Handling becomes unpredictable.
Key definitions:
- GTW (Gross Trailer Weight): Total weight of the loaded trailer.
- TW (Tongue Weight): Downward force at the hitch point.
- GVWR (Gross Vehicle Weight Rating): Max weight your tow vehicle can weigh fully loaded.
- GTWR (Gross Trailer Weight Rating): Maximum your hitch is rated to tow.
- TW Rating: Maximum tongue weight your hitch class is rated for.
Hitch classes (North American standard):
- Class I: Max 900 lb GTW, 90 lb TW — small cars, light cargo
- Class II: Max 3,500 lb GTW, 350 lb TW — mid-size cars
- Class III: Max 8,000 lb GTW, 800 lb TW — most trucks, SUVs
- Class IV: Max 14,000 lb GTW, 1,400 lb TW — heavy duty trucks
- Class V: Max 20,000 lb GTW, 2,000 lb TW — commercial use
Always check both your vehicle’s tow rating AND the hitch rating — the lower limit applies.
This calculator works in both kg and lb.