How to Measure Entry Locks and Deadbolts

Pull out a sturdy measuring tape with a button extraction feature. As you pull out the tape, it should lock into place.

Measure from the edge of the door all the way to the first edge of the door paneling or glass. This is called the door stile.

Note the door hand, or whether the door requires left or right handle on the outside or inside of the door. This will determine the type of hardware you purchase for the door.

Measure the width of the door border, also known as the door's thickness.

Measure the backset dimensions as follows: Measure from the edge of the door to the center of the pre-drilled holes. If you have two pre-drilled holes, measure from the center of the top pre-drilled hole to the center of the bottom pre-drilled hole. Finally, measure from the floor to the center of the bottom pre-drilled hole. Take these measurements with you to your local hardware store to determine the type of hardware you need to purchase.