To many variables. That is like asking how long is a piece of string.
width of car door
The width of a standard single-car garage door is typically 8 to 9 feet wide.
The standard width of a one-car garage door is typically 8 to 9 feet wide.
The standard width of a single car garage door is typically 8 to 9 feet wide.
the internal width of the car from one internal door panels to the opposite panel
Generally 8' or 9'
Normal width of a single car garage is 8' feet. Normal width of a double car garage is 16' feet. These answers are for doors typically found in the USA.
You'll need to get a nonstandard garage door (not single-car width), so that may be very hard to find.
8 or 9 foot, either one is common.
The most often chosen width of a front door is 36".
The standard double car garage door is 16' wide x 7' high. A two car garage should typically be a minimum of 20' wide (inside) to allow the doors to open. 22' to 24' width is preferred.
Width (excluding door mirrors): 66.1 in. (1.68m) Width (including door mirrors): 76.4in. (1.94m).