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    RoamWorthy

    How the towing calculator works

    What we check

    85% guideline - The Caravan and Motorhome Club recommends that your caravan's loaded weight (MTPLM) should not exceed 85% of your car's kerbweight. This is a guideline, not a legal requirement, but it is widely recognised as best practice for safe, stable towing. Especially for less experienced drivers.

    Legal maximum braked towing capacity - Every car has a manufacturer-stated maximum braked towing limit. The caravan's MTPLM must not exceed this figure. This is a legal requirement.

    Gross Train Weight (GTW) - The combined weight of your car and caravan must not exceed the car's GTW rating. We check this when the data is available.

    What we do not do

    This tool is not legal advice. Always confirm your vehicle's limits from the VIN plate or manufacturer handbook before towing.

    We do not account for passengers, luggage, or aftermarket modifications that may affect your car's payload or towing capacity.

    Results are based on the data available and may not reflect every variant or special edition.

    Data sources and accuracy

    DVLA vehicle data - When you enter a registration number, we retrieve verified vehicle information including kerbweight and towing limits where available.

    Manufacturer specifications - We maintain a database of caravan and motorhome model specifications sourced from manufacturer brochures and official data.

    Manual entry - Some vehicles may not have complete data. In those cases, you can enter values manually from your handbook or V5C document.

    Definitions

    Kerbweight
    The weight of the car with a full tank of fuel and all standard equipment, but without passengers or luggage.
    MTPLM (Maximum Technically Permissible Laden Mass)
    The maximum loaded weight of the caravan, including all equipment and personal belongings.
    MIRO (Mass in Running Order)
    The weight of the caravan as delivered from the factory, with standard equipment and full gas/water.
    Noseweight
    The downward force exerted by the caravan's coupling on the tow ball. Must stay within both the car's and caravan's limits.