# Towing Rating Cross-Check Calculator — United States

> Cross-check multiple entered weight ratings instead of treating the advertised maximum tow rating as the only limit. USD planning view; stated limitations apply.

Page: https://askcalculators.com/us/towing-capacity/
Definition: https://askcalculators.com/us/towing-capacity/definition.json
JSON Schema: https://askcalculators.com/us/towing-capacity/schema.json
Version: 20.16.0
Maintained by: AskCalculators (software project; not a credentialed reviewer)
Qualified review: pending. Automated checks do not establish professional approval.
Page status: Live
Review status: Pending

## Use
Open the calculator page and enter values. Query-string parameters can restore and bookmark a calculation.
Example: https://askcalculators.com/us/towing-capacity/?unitSystem=imperial&gcwr=13227.735731092655&loadedVehicle=5511.5565546219395&towRating=6613.867865546327&payloadRemaining=1102.311310924388&tonguePercent=12&hitchTrailerLimit=6613.867865546327&hitchTongueLimit=771.6179176470715

## Inputs
- unitSystem: Measurement system; type=select; optional; default=imperial; values=imperial|metric
- gcwr: Manufacturer gross combination weight rating; type=number; required; default=13227.735731092655; min=0; max=2204622621848.776
- loadedVehicle: Actual loaded tow-vehicle weight before trailer tongue; type=number; required; default=5511.5565546219395; min=0; max=2204622621848.776
- towRating: Configuration-specific manufacturer trailer rating; type=number; required; default=6613.867865546327; min=0; max=2204622621848.776
- payloadRemaining: Actual remaining vehicle payload; type=number; required; default=1102.311310924388; min=0; max=2204622621848.776
- tonguePercent: Measured/expected trailer tongue-weight fraction; type=percent; required; default=12; min=0; max=50
- hitchTrailerLimit: Hitch trailer-weight rating; type=number; required; default=6613.867865546327; min=0; max=2204622621848.776
- hitchTongueLimit: Hitch tongue-weight rating; type=number; required; default=771.6179176470715; min=0; max=2204622621848.776

## Outputs
- combinationLimit: Trailer allowance from combination rating; format=number
- payloadLimit: Trailer allowance from remaining payload; format=number
- hitchLimit: Trailer allowance from hitch tongue rating; format=number
- limitingWeight: Lowest entered arithmetic trailer allowance; format=number; primary

## Formula
arithmetic trailer allowance = minimum(combination rating − loaded vehicle, vehicle tow rating, remaining payload/tongue fraction, hitch rating, hitch tongue rating/tongue fraction).

Inputs are converted to canonical units before evaluating this stated formula.

## Rules
- Empty optional inputs are undefined, not zero.
- Hidden conditional inputs are ignored.
- Do not invent missing required inputs.

Notice: Illustrative defaults are not local quotes or verified legal rules. Dated reference components and user-entered assumptions are explicitly distinguished. Professional review is pending.