Find Your Backset

What is a your door’s backset, and how do you find it?

Your backset is a important dimension of your door to know when you need to purchase a lock. The backset is the distance the center of the lock is set back from the edge of the door. There are two standard backsets 2 3/8″ (two and three eighths inch) and 2 3/4″ (two and three quarters inch).

Stretch a tape measure (horizontally) from the edge of the door to the top (center) of your lock.

 

The distance the center of the lock is set back from the edge of the door is called the back set.

Still need help?

No problem, follow along to make this template.

The way your door swings open will determine if this template is applied to the inside of the door or outside of the door.

 

Make marks at 2 3/8″ and 2 3/4″

 

Your template should reveal if your door has the short backset or the longer backset. 2 3/8″ is short & 2 3/4″ is long.
Tape your template to the door, and decide which mark the top (center) of the lock touches. This door is 2 3/8″, this is the shorter backset.
close up shot of our 2 3/8″ example

Remember your backset will be one of these two choices. You wont be able to purchase a lock in a different size, it is one or the other. Most entry grade locks have adjustable backsets. Non-adjustable backsets have the potential to be stonger and last longer. You find that premium locks never have adjustable backsets, this is for strength and durability.