Caravan Towing Weight Calculator (UK)
Check your car and caravan against MTPLM, towing limits, nose weight, MAM and gross train weight, plus the 85 % guideline.
Example rig — replace every number with your own.
Towing weight check
Uses the numbers you enter from your plates and manuals — it can't check them for you. Weigh your loaded rig at a public weighbridge or CAT scale. Rules vary by state and country. Not legal advice.
The laden caravan must stay within its MTPLM and your car's towing limit; the nose weight within the car's and towbar's limits; the car (with nose weight) within its MAM; and car plus caravan within the gross train weight. The Caravan and Motorhome Club suggests keeping the caravan to 85 % of the car's kerbweight if you are new to towing.
How it's calculated
• Car with nose weight = laden car + nose weight
• Train weight = car with nose weight + laden caravan − nose weight
• Weight ratio % = (laden caravan ÷ car kerbweight) × 100
Frequently Asked Questions (FAQ)
Is the 85 % rule the law?
No. It is guidance from the Caravan and Motorhome Club for stability (up to 85 % for beginners, perhaps 90 % for experienced towers, never above 100 %). The legal limits are your plated and handbook weights.
Where do I find gross train weight?
In the handbook or specification sheet, and often on the manufacturer's plate (nidirect).
Do trailers over 750 kg need brakes?
nidirect: "Any trailer weighing over 750kgs must have a working brake system."
Sources
- The Caravan and Motorhome Club — Buying a towcar
85 % / 90 % / never > 100 % guidance; MTPLM; gross train weight
- nidirect — Towing safety information
MAM, gross train weight on manufacturer's plate, > 750 kg needs brakes
- GOV.UK — Towing with a car
Licence rules information (rules differ by test date)
Last reviewed: 2026-10-26
Built and maintained by Numberwright. The checks follow the definitions published by motoring bodies, transport departments and vehicle makers listed under Sources. Found a mistake? Contact details coming soon.
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