What are some common string widths and curvatures?

4 String Bass Pickups 
The most common string width (center of low string to center of high string) for these is known as
“Fender width” – 3/4″ per string / 2-1/4″ total
or 57mm total string width at the bridge.
5 String Bass Pickups 
From the beginning these instruments were made in a wide range of string widths.
The most common widths are:
66mm,
70-72mm and
76mm total string width at the bridge.
6 String Bass Pickups 
From the beginning these instruments were made in a wide range of string widths.
The most common widths now are:
82mm,
86mm,
92mm and
96mm total string width at the bridge.
7 String Bass Pickups 
These instruments are just establishing themselves. We make pickups for many instruments being built with 103 – 108mm total string width at the bridge.
Fingerboard Curvature 
In general, modern instruments have lower fingerboard curvature than earlier ones. Fingerboard curvatures fall into three categories: “nearly flat” (meaning 14″ radius or larger), “Gibson-like” (meaning approximately 12″ radius) and “Fender-like” (meaning early Fender, approximately 10″ radius).