How to measure Euro Cylinder Lock

This how to video shows you how to accurately measure a Euro cylinder lock. While there’s a wide range of Euro cylinder lock sizes available, there’s 3 standard methods that you need to know to accurately measure the cylinder - in order to select the right lock size for your needs. We take you through each step, including details on the tools you’ll require to establish the measurements. If you would like any additional information please visit our website safe.co.uk and speak with our friendly customer care team.

[@Autonomous1969]

I think the Yale way is best. They state all their locks as for example 40-10-45 where the 10 is the middle lock.

[@josephmusembi4391]

Thanks, that's very helpful.

[@neillaw]

So, for a 55/40 I take that as 55 exterior and 40 interior, however the label printed on the box I received states 55/40 but the digram shows 40 then 55
Obviously not an issue usually, however the deterrent and presumably security is more on the exterior side?

[@thesafeshop]

For high security cylinders, they usually have a snap line on the exterior side. This is a key indicator as to which side should face externally once installed. The side with a snap line snaps off sacrificially during an attempt by a burglar to snap the lock, and makes it impossible to then manipulate the lock cam. Some lower security cylinders, that don't include anti-snap features, are reversible and can be install either way around.

[@neillaw]

@@thesafeshop I was wrong about the definition, apparently 55/40 is interior/exterior, however the diagrams always show exterior - interior, a confusing logic IMO!

[@rml442]

What does it mean if it says 30/10/30 - 70mm? Is it the same as 35/35?

[@thesafeshop]

When a measurement is displayed as 30/10/30, it takes the centre cam into consideration. The Centre cam is 10mm and there is 30mm either side of this centre cam. The total length is 70mm. When a cylinder displays the measurements of 35/35, the total length is also 70mm but dimensions refer to the measurement to the retaining screw from either side.

[@venkatesanmunusamy3483]

What about dia sir.?

[@thesafeshop]

We don't mention diameter because it is a standard size. This never changes on Euro Cylinders and is determined by the Euro case it is being used with. The only dimensions you need to measure are the internal and external size form the centre retaining screw of the cylinder.