Marine Trailer Weight Arithmetic
Add your boat, engine, gear, trailer and user-density fuel masses, then show arithmetic towing and optional nose margins.
A QUICK WALKTHROUGH
How to use this tool
- Enter nonnegative component masses and fuel litres, plus your positive fuel density.
- Enter your towing limit and tongue percentage; optionally enter a nose limit, then calculate.
- Calculate, then copy the report or download TXT.
Calculation
Fuel kg = litres × user density. Total = body + engine + gear + empty trailer + fuel. Towing margin = entered towing limit − total. Tongue kg = total × entered percentage/100. Nose margin = optional nose limit − tongue kg.
What the result covers
Only entered masses and limits are used. No fuel density or tongue percentage is supplied or recommended. Positive margins do not prove towability, axle compliance, gross-train limits or legal compliance. Real loading, measured masses and all applicable vehicle, hitch and trailer limits require separate review.
Local processing
Inputs remain in your browser. Copy and TXT download contain your inputs, results, formula and scope note.
GOOD TO KNOW
Common questions
Can margins be negative?
Yes. A negative result means the arithmetic mass exceeds that particular entered limit; it is not a full towing assessment.
What if I leave the nose limit blank?
The tongue mass is still calculated, but the optional nose margin is marked not provided. Zero is a supplied limit, not a blank.