If you dont have any hardware on your door just measure from the edge of the door to the center of the bore hole the large hole where the door knob assembly is mounted.
How to measure door handle backset.
2 3 8 inches and 2 3 4 inches.
Most door handle sets feature a 2 3 8 or 2 3 4 backset.
In order to do this measure from the edge of the door to the centre of the door knob handle the industry standards are usually 44 mm 57mm 82mm 107mm 130mm.
To avoid chafing or having to drill new holes in your door make sure you measure accurately the distance from the front face of the latch to the centre of the square hole for the spindle.
A backset is the distance from the center of the cross bore to the edge of the door.
Whether you have lever on rose door handles or lever on backplate your interior door handles can house any latch how to measure your latch when buying a tubular mortice latch for your door handle.
Standard backsets are either a 2 3 8 backset or 2 3 4 backset.
The two standard backset measurements in north america are 2 3 8 inches and 2 3 4 inches.
To determine the backset on your door measure the distance from the outer edge of the door to the center or highest point of the bore hole.
Pack your locks with a 2 3 8 inch or 2 3 4 inch latch depending on which backset you specify.
The most common backset is 2 3 8 but 2 3 4 is also quite common usually used on exterior doors.
Ideally you will try and choose the backset measurement that sites the door handle in the middle of the door stile.
In the united states there are two common backsets for residential door locks.
Whilst there is no keyhole to consider on a mortice latch you still need to consider the backset of the follower for the handles or knobs you have on the door.
A shorter backset is recommended if you re using a glazed door.
The backset is the distance from the edge of the door to the center of the 2 1 8 inch bore hole.