What is the difference between GVWR and GCWR?

GVWR is the maximum allowed weight of the loaded tow vehicle by itself, including passengers, cargo, and the trailer tongue weight pressing down on it. GCWR is the maximum combined weight of the loaded vehicle plus the loaded trailer. Both must be respected at the same time.

Why does tongue weight count against the vehicle?

The trailer tongue presses down on the hitch, transferring 10 to 15 percent of the trailer weight onto the rear of the tow vehicle. That load adds to the vehicle's own weight, so it counts against GVWR as well as the hitch rating, which is why both checks include it.

What is the ideal tongue weight?

Tongue weight should be roughly 10 to 15 percent of the loaded trailer weight. Too little causes dangerous trailer sway, while too much overloads the hitch and rear axle. The tool flags when you fall outside that band so you can redistribute the load.

Can I exceed max tow capacity if I am under GCWR?

No. The limits are independent and all four must be satisfied. The max towing capacity, hitch rating, GVWR, and GCWR each guard a different failure mode, so exceeding any single one is unsafe and usually voids warranty and insurance regardless of the others.

Does this account for weight-distributing hitches?

It checks the raw rated limits you enter. A weight-distributing hitch can raise the allowable tongue and tow figures, so enter the ratings that apply with your specific hitch setup, and follow the manufacturer's instructions for when one is required.

Towing Capacity Checker

Towing safely means staying under several limits at once, not just the headline tow rating. This checker takes your vehicle and trailer weights and verifies all four governing limits simultaneously, flagging any that are exceeded.

How it works

Four independent limits are evaluated, each guarding a different failure mode:

1. trailer weight  ≤ max towing capacity
2. tongue weight   ≤ hitch tongue-weight rating
3. loaded vehicle  ≤ GVWR   (curb + tongue + occupants/cargo)
4. combined weight ≤ GCWR   (loaded vehicle + trailer)

It also checks the advisory stability rule that tongue weight should be 10 to 15 percent of the loaded trailer weight — too little invites sway, too much overloads the rear axle.

Example and notes

A truck with a 7000 lb GVWR and 6500 lb curb-plus-load, towing a 5000 lb trailer with 600 lb of tongue weight, must check that the trailer is under the max tow rating, that 600 lb is under the hitch rating, that 6500 plus 600 stays under GVWR, and that the full combined weight stays under GCWR. Enter every figure in the same unit, take ratings from the door-jamb sticker, and remember that staying under all four limits is the legal and safe minimum — also confirm your tyres’ load ratings.