About this tool
Towing & Payload Capacity Calculator is a free, in-browser tool that checks whether your loaded truck and trailer stay inside the manufacturer's weight ratings. Enter the vehicle's ratings and the weights you plan to carry and pull; it returns your payload capacity, how much payload is left, and the heaviest trailer you can legally tow — with pass/fail flags. All calculations run locally in your browser.
Payload capacity is GVWR − curb weight. Available payload subtracts what rides in the truck: payload capacity − passengers − cargo − trailer tongue weight (the tongue load presses down on the hitch and counts against payload). Maximum trailer weight is GCWR − (curb + passengers + cargo), the combined-rating headroom left for the trailer. Two checks then run: available payload must be at least zero, and your trailer must weigh no more than the maximum.
Use it before a big tow to make sure you are not over GVWR or GCWR — the two ratings that matter most for safety and legality. If either check fails the tool warns you so you can shed cargo, redistribute weight, or downsize the trailer. Always confirm the exact ratings on your door-jamb sticker and towing guide.