Minimum Shower Door Width

At the top and at the bottom.
Minimum shower door width. The international residential code specifies that the minimum finished width for a shower access opening is 22 inches. The standard shower door size is between 22 inches and 36 inches. When designing your shower enclosure keep in mind that each glass panel needs to be at least 4 1 2 wide which is the minimum width for tempering glass and supporting the hardware.
The height is not specified but one would expect that it would need to be tall enough to enter without hitting your head the bar at the top of the door if one happens to be present. This means that if the door width is 32 inches you must have a passage of 32 inches wide and 32 inches long of clear space leading into the bathroom. The minimum interior shower size is 30x30 inches or 900 square inches in which a disc 30 inches in diameter must fit.
Also the door will need to be a minimum of 22 wide and no more than 36 wide. A shower door needs enough clearance in the bathroom to open completely. The amount of space you have around the shower will determine which direction the door opens.
Measuring for a shower door. Measure in two places. Minimum width of glass panels.
You will need a minimum of 21 inches of. The distance from the centerline of a toilet and or bidet to any bath fixture wall or other obstacle should be at least 18 inches.