How to Measure a Cam Lock | Cam Lock Size Guide
Cam locks are commonly used on lockers, cabinets, drawers, letterboxes and cupboards.
Although most cam locks look similar, they come in different lengths, head styles and fixing types, so it’s important to measure your existing lock before ordering a replacement.
This guide will show you exactly what to check so you can find the correct cam lock quickly and easily
Step 1 – Measure the Barrel Length
The most important measurement is the barrel length of the cam lock.
To measure this:
- Remove the cam lock from the door, drawer or cabinet.
- Measure the threaded section of the barrel from the back of the face to the end of the thread.
This measurement determines whether the lock will fit through the thickness of the door or panel.
Common cam lock lengths include:
Selecting the correct barrel length ensures the cam lock sits securely in place and operates properly.
Step 2 – Check the Cam (Tailpiece)
The cam, sometimes called the tailpiece, is the metal arm attached to the back of the lock.
When the key is turned, the cam rotates to secure or release the door or drawer.
Cam locks can have different cam styles such as:
- Straight cams
- Offset cams
- Hooked cams
In many cases, the cam can be removed and reused with the new lock if the fixing hole is the same size.
Step 3 – Identify the Head Style
Cam locks are available with different head shapes, which sit on the outside of the cabinet or door.
The most common head styles include:
- Round head
- Square head
- Hex head
Checking the head style ensures the replacement lock fits neatly into the existing hole.
Step 4 – Check the Fixing Type
Most cam locks are secured using one of two fixing methods.
Nut Fixing
A threaded nut is tightened on the back of the cam lock to hold it in place.
Clip Fixing
A metal fixing clip slides onto the back of the lock to secure it.
Make sure the replacement cam lock uses the same fixing method as your existing lock.
Keying Options
When choosing a cam lock, you may also need to select how the locks are keyed.
Keyed to Differ
Each lock is supplied with its own unique key.
Keyed Alike
Multiple locks can be opened using the same key. This is useful if you want one key to operate several cabinets or lockers.
Master Keyed
Each lock has its own key, but a master key can open all locks within the system. This is commonly used in offices or shared buildings.
( All L&F camlocks are supplied pre mastered).
Measuring your Cam Lock

Cam Lock Head Shapes
Methods of fixing Cam Locks metal/plastic

Need Help Choosing the Right Cam Lock?
If you are unsure which cam lock you need, our team is happy to help please call us on 0330 174 0851
Simply send us:
- A photo of your existing cam lock
- The barrel length measurement
- Details of the cam on the back of the lock
Our experts will help you identify the correct replacement.
Once you have determined the correct lock you need you are now ready to choose an from our range. Here at Lock Shop Direct we only stock leading brands.