Check your towing combination before buying a caravan
This caravan towing weight calculator organizes the margins between your planned trip weights and the individual ratings of your tow vehicle, trailer and coupling equipment.
It is useful when comparing a caravan with a vehicle you already own, preparing for retirement travel, or checking how family members and extra equipment affect a planned combination.
A headline towing capacity is only one of several limits, so the calculator shows eight separate comparisons and identifies missing information.
Vehicle gross mass, combined mass, trailer gross mass and vertical coupling load describe different constraints.
A generous margin in one row cannot compensate for an exceeded limit elsewhere.
Save the input and result table to make a more specific request to the vehicle manufacturer, caravan builder or hitch installer before committing to a purchase.
What decision does the result support?
Identify which entered rating is insufficient and which specification or measurement still needs confirmation.
The result supports a discussion about the proposed combination; it does not certify that a vehicle can safely or legally tow it.
For purchase, insurance, storage and running costs, use the separate camper and caravan ownership cost calculator.
Korea-related scope: this page uses kilograms and Korean regulatory context reviewed on September 11, 2026.
The English interface uses the same calculation function as the Korean interface.
No foreign licensing rules or automatic vehicle specifications are substituted.
Understand GVWR, GCWR and tongue load
Vehicle and combination ratings
GVWR is the maximum gross mass rating of the vehicle itself.
It is compared with the vehicle carrying its occupants, cargo and the load transferred through the coupling.
GCWR, also called GCM in some documentation, limits the total vehicle and trailer combination.
It does not replace the vehicle rating.
Whole trailer and coupling load
The whole trailer mass includes both the part supported by its wheels and the part supported at its coupling.
Tongue load, also called nose load, is the downward load on the vehicle hitch.
It is already part of the whole trailer mass.
Model year, powertrain, towing package, tires, occupancy and trailer brakes can affect which manufacturer rating applies.
Do not copy a number from another owner or a similar-looking vehicle advertisement.
Read your registration documents, rating plates and the manual for the exact configuration together.
If the documents disagree, ask the manufacturer which figure and unit apply instead of choosing the largest number.
Enter actual masses without counting anything twice
- Vehicle base B: use the vehicle before coupling the caravan.
Check whether fuel and existing equipment are included.
People or equipment already included in this reading must not be added again in the next fields.
- Additional passengers P and cargo C: add only occupants, luggage and extra hitch hardware missing from B.
If the vehicle was already weighed ready for the trip, enter 0 for each fully included additional category.
A blank means unknown, rather than zero.
- Trailer reading W: select either the whole trailer including tongue load, or just the sum of its axle readings while coupled.
In axle mode, the function adds H to recover whole trailer mass.
After changing this selection, re-enter W using the matching measurement basis.
- Tongue load H: use a measurement with the same water, luggage and equipment arrangement.
Moving cargo changes the loading assumption, so an earlier tongue-load measurement may no longer describe the new setup.
Do not enter a hitched vehicle reading as B
The calculator adds tongue load to an unhitched vehicle base.
Entering a vehicle scale reading taken while hitched would count that transferred load twice.
Prepare an unhitched reading and record the fuel, people and equipment included in it in the source notes.
Formulas: count tongue load once in combined mass
- Unhitched vehicle V = B + P + C
- Whole trailer T = W; for axle-only input, T = W + H
- Hitched vehicle = V + H
- Combination G = V + T = (V + H) + (T − H)
- Rating margin = entered limit − compared mass
- Excess = max(compared mass − entered limit, 0)
- Observed tongue-load percentage = H ÷ T × 100
Combined mass includes each physical mass once.
Adding H again after using whole trailer mass would overstate the combination by H.
Omitting H when checking vehicle GVWR would make the opposite mistake: it would omit the load carried through the hitch.
This simple static relationship applies to a conventional ball hitch without weight distribution.
Weight-distributing hitches and semitrailers require a separate measurement review.
Review all eight ratings separately
Vehicle and trailer mass limits
Compare vehicle GVWR with hitched vehicle mass and GCWR with combined mass.
Compare both vehicle towing capacity and the trailer gross mass rating with whole trailer mass.
The trailer has its own loading limit, even if the tow vehicle is substantially larger.
Hitch and vertical-load ratings
Compare the hitch assembly towing rating with whole trailer mass.
Compare vehicle, hitch/ball and coupler vertical ratings separately with the same measured H.
Where an assembly contains several components, confirm the lowest applicable rating with the installer.
An accessory carrier such as a bicycle rack can load the hitch at a different position and have a different rating from trailer towing.
Also distinguish braked and unbraked trailer limits.
Never fill an unknown rating with a convenient large value or a zero merely to finish the table.
A documented zero limit is treated as no permitted load for that comparison; a blank is treated as missing information.
Worked example: verify the mass table
These are fictional inputs for checking the arithmetic, not specifications for a vehicle or hitch offered for sale.
Enter B = 2,000 kg, P = 150 kg, C = 100 kg, whole trailer W = 1,400 kg and H = 100 kg.
The unhitched vehicle is 2,250 kg, the hitched vehicle is 2,350 kg and the combination is 3,650 kg.
Trailer axles carry 1,300 kg; entering 1,300 kg in axle-only mode gives the same whole trailer mass.
Eight fictional limits, compared masses and margins in kilograms| Check | Limit kg | Mass kg | Margin kg |
|---|
| Vehicle GVWR | 2,800 | 2,350 | 450 |
| Combination GCWR | 4,500 | 3,650 | 850 |
| Vehicle towing | 2,000 | 1,400 | 600 |
| Trailer gross rating | 1,600 | 1,400 | 200 |
| Hitch towing | 1,800 | 1,400 | 400 |
| Vehicle vertical | 150 | 100 | 50 |
| ★ Hitch vertical | 120 | 100 | 20 |
| Coupler vertical | 130 | 100 | 30 |
The smallest rating margin is 20 kg at the hitch vertical-load rating.
The observed tongue-load percentage is about 7.14%, but the calculator does not decide whether this is appropriate for your caravan.
Consult the relevant manufacturer instructions.
Loading the fictional example leaves the measurement and rating confirmations unchecked.
If H changes to 130 kg, the 120 kg hitch vertical rating is exceeded by 10 kg, while combined mass remains 3,650 kg.
Interpret the status and smallest margin
Check exceedances, unknowns and zero margins
A negative margin means the entered mass exceeds the entered rating.
Use the excess amount to identify the specification that needs attention.
Even when every number is present, the review remains pending until the relevant documentation and measurements are confirmed.
A margin of exactly zero is shown separately as at the limit; the calculator does not invent an extra tolerance.
The overall minimum appears only when all eight rows can be calculated.
It is not an allowance for extra cargo.
A 20 kg vertical-load margin and a 200 kg trailer gross-mass margin constrain different parts of the combination.
Adding 20 kg of cargo does not necessarily add 20 kg at the hitch; its position can increase or decrease the load transferred there.
After any change, weigh the revised arrangement and compare each limit again.
A favorable static result still leaves axle loads, tire ratings and the other separate checks unresolved.
Use the review for buying and trip preparation
- Identify the vehicle, caravan, hitch and coupling model/year and confirm the conditions attached to their documents.
- List the intended occupants, water, luggage and equipment, separating items already included in the base reading.
- Use estimates for an initial purchase discussion, leaving the actual measurement confirmations unchecked.
- Weigh the setup ready for the trip and align total, axle-only and tongue-load measurement bases.
- Save the CSV with source notes and unknowns for a manufacturer or installer review.
If more family members join a trip, both vehicle and combination margins can decrease.
Adding a battery or water container to the caravan changes its total mass and calls for another tongue-load measurement.
Replacing a hitch with a higher-rated one does not automatically increase the vehicle or coupling rating.
Comparing an empty caravan with its fully equipped trip condition can reveal omitted accessories before a purchase contract is signed.
Limits and cautions
- Only conventional ball-hitch static masses are calculated.
Weight-distributing hitches, semitrailers and unknown configurations are outside scope and results are withheld.
- Front/rear axle loads, tire ratings, load placement, hitch extension length, slopes, braking, crosswinds and sway are not calculated.
An individual axle may be overloaded even when vehicle gross mass is below its limit.
- Driver licensing, road access, modification approval, inspection and insurance coverage are separate matters.
Confirm the requirements with the relevant authorities and providers before departure.
- A zero tongue-load reading is not treated as favorable merely because it is small.
The review stays pending while measurement method and load placement are rechecked.
The input range of 0–100,000 kg and two decimal places is an interface boundary, not a legal load allowance.
Convert tonnes to kilograms and do not enter pounds or units of force as though their numerical values were kilograms.
Readings near a limit deserve a review of the original measurement and loading variability with the manufacturer or weighing provider.
A change in braking equipment or vehicle options also requires rechecking which rating applies.
Frequently asked questions
Is being below the maximum towing capacity enough?
It is not enough to complete this review.
Check vehicle GVWR, combination GCWR, trailer and hitch ratings, and each vertical-load limit separately.
Should tongue load be added to the combination as well?
It is already included in whole trailer mass.
Add the unhitched vehicle to the whole trailer, or the hitched vehicle to trailer axle mass only.
Can I use a fixed percentage to estimate tongue load?
This tool does not infer actual tongue load from a universal percentage.
Measure it under the intended loading conditions and consult the vehicle and caravan instructions.
Can a rating be left blank?
Yes, it remains unconfirmed.
Other calculable rows are displayed, but the overall minimum and completed review are withheld.
Will moving a water container rearward solve an overload?
Load placement affects the coupling, axles and driving behavior.
Follow manufacturer instructions and reweigh after a change instead of moving cargo solely to lower one number.
Does the calculator look up vehicle specifications?
No automatic model ratings are applied.
Vehicles with the same model name may differ by configuration; use your own registration, plates and manual.
Can I use the same formulas with a weight-distributing hitch?
The simple tongue-load transfer used here is not applied to that setup.
Review the specific manufacturer instructions and axle measurements separately.
What does the CSV contain?
The file includes input values, confirmations, source and weighing notes, the mass table, example status and scope.
It is saved locally for your manufacturer or installer discussion; the calculator does not send it to a provider.
Official sources and the 2026 context
Sources reviewed September 11, 2026.
Article 20 of the Korean Rules on the Performance and Standards of Motor Vehicles and Motor Vehicle Parts was checked directly through the National Law Information OPEN API.
The current rule is law ID 007939, MST 288083; the rule and returned article are effective July 10, 2026.
Installation requirements are separate checks, not a formula for a universal towing allowance or tongue-load percentage.
- Korean vehicle standards, Article 20: coupling installation requirements
- Chevrolet Real New Colorado owner manual: printed pages 259–263, separate mass ratings, tongue-load accounting and trip-ready weighing
- Tesla Model Y Korean owner manual: trailer versus accessory loads and configuration-specific ratings
These manuals support the concepts and verification process.
Their model-specific numbers are not universal inputs for other towing combinations.
Recheck the actual ratings and measurement assumptions when the model year, equipment, options or manual version changes.
Prepare a weight table for your purchase discussion
Enter the specifications and measurements you have, then use the remaining blanks as a list of information to obtain.
Once the document conditions and actual weights are confirmed, save the CSV so that you and the manufacturer or installer can review the same numbers.
Return to weight inputs