How we calculate
We combine public vehicle data from the RDW (the Dutch vehicle authority) with manufacturer figures for boot capacity, and convert those into standard crates of beer of 40 × 30 × 26 cm. Then we check whether the car is actually allowed to carry that weight.
Where does the data come from?
Make, model, body type, year, wheelbase and weights come live from RDW Open Data, the public vehicle register of the Dutch Vehicle Authority (Rijksdienst voor het Wegverkeer). Boot capacity isn't in the register. That comes from our own table of manufacturer figures for 366 car models and 36 vans, in litres according to the VDA standard.
How big is a crate of beer?
We use a standard Dutch crate (krat) with 24 bottles of 30 cl: about 40 × 30 × 26 centimetres, so 31.2 litres per crate. A full crate weighs about 17 kilos.
Why not just divide the litres by the size of a crate?
Manufacturers measure boot capacity with 1-litre blocks that also fill corners, wheel arches and the space under the floor. A crate doesn't fit there. So we count 50% of the stated litres with the rear seats up, 45% with them folded (sloping seatbacks, sloping roof) and 70% in the square cargo area of a van. We always round down.
How many crates am I allowed to carry?
Besides space, we look at weight. The RDW registers the maximum permitted mass and the kerb weight of every car; the difference is what you may carry, passengers included. Divided by 17 kilos per crate, that gives the maximum number of crates. For licence plate checks we show the lower of space and weight.
What if my model isn't in the table?
Then we estimate the boot capacity from the wheelbase (as a measure of the car class) and the body type in the register. That result is clearly marked as an estimate.
How accurate is this?
It's a well-founded estimate, not a guarantee. That's why there's always a ± in front of the number of crates. Manufacturer figures vary by version, and how you stack makes a big difference. Allow a margin of a crate or two. And a full boot is never a reason to drink and drive.
Does it work with foreign licence plates?
No. We use the Dutch vehicle register, so it only works for cars with a Dutch licence plate (kenteken). If your car has foreign plates, look up your model in the overview of all cars.
Do you store my licence plate?
No. Vehicle data is fetched live from the RDW for every check; licence plate data is public in the Netherlands. If you send feedback, we pass the licence plate to our server once to look up the car; we then only keep the model details (make, type, year, dimensions), not the licence plate. We count visits anonymously with Umami, a cookieless analytics tool on our own server: no cookies, no personal data and no licence plates.
How can I help?
Under every result and on every model page we ask whether it's right. If you actually tried it, tell us how many crates went in and how the car was set up. Even better: measure your boot. With those measurements we work out the layout crate by crate, for everyone with the same car. One measurement counts as reliability C; only when several measurements agree does it go up.
About this site
Hoeveelkratten.nl is a project by van Melzen Automatisering.
For developers and AI assistants
The same result is available as JSON at https://hoeveelkratten.nl/api/kratten?k=PLATE. All models and their figures are in a single file: https://hoeveelkratten.nl/llms-full.txt.
Updated on