The most common angle for parking lot stalls is the 60-degree angle, due to the ease of pulling in and out of the stalls and the width it leaves for traffic lanes. The 45-degree stall is preferable for tight spaces, while the 90-degree angle allows the highest car capacity.
The design of a parking lot usually involves an aisle, or traffic lane, with a row of parking stalls either to one side or both. With 90-degree-angle stalls, the aisles are wide enough to allow two-way traffic, but entering and exiting the stalls is more cumbersome. Other angles require aisles with one-way traffic to allow cars to pull in and out of the stalls in a common direction.