What is door handing?
Look at the door from the hinged side. If the hinges are on the right it is right handed door, and if they are on the left, a left handed door.
A simple way to determine if the door (and lock) is left or right handed is to look at the door from the hinge side.
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Left hand
The hinges are on the left side.
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Right hand
The hinges are on the right side.
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