Why measuring your lock matters

Not all locks are the same size. Even if two locks look similar, small differences in measurements can affect whether the lock fits correctly. Measuring your existing lock in advance helps avoid mistakes and makes replacement much easier.

What you need

Before you start, have the following ready:

• A measuring tape or ruler

A screwdriver if you need to remove the lock

1. Backset - Point A

The backset is the distance from the edge of the door to the centre of the keyhole or cylinder hole.
This is one of the most important measurements when replacing a lock.

2. Distance between handle and keyhole - Point B

Measure from the centre of the handle spindle to the centre of the keyhole or cylinder.
This helps identify the correct lock body and handle alignment.

3. Front plate size - Point C

Measure the metal plate on the edge of the door:

• Total length
• Total width

4. Lock case depth and height - Point D

If possible, remove the lock and measure the body of the lock:

• Total depth
• Total height
• Thickness

5. Cylinder size 

If your lock uses a euro cylinder, measure from the centre fixing screw to:

• The outside end of the cylinder - A
• The inside end of the cylinder - B

This gives you the cylinder size, for example 30/30, 35/45, etc.

• Bring the old lock or cylinder with you if possible
• Take clear photos of the lock from the front, side, and edge of the door
• Note whether the door is wooden, aluminium, or metal
• Mention whether the door opens left or right if relevant

If you are unsure about any measurement, do not worry. Bring your measurements, photos, or the old lock to our shop and we will be happy to help you find the correct replacement.

Getting the right measurements first means a faster, easier, and more accurate purchase.