This calculator is in development. It works, but it has no error checking, so if you enter stupid and unrealistic measurements you'll end up with a stupid and unrealistic set of results.

Usage Notes:
i) If you don't know the 'Rim Edge Width' measurement, most Alloys wheels are between 11-13mm and Steels come in around 6-9mm. If in doubt, take a guess.
ii) When it says 'OR' this means that you do need at least one of the pieces of data to get a complete set of dimensions.
iii) Soon i'll add info about each dimension, but for now please refer to the Wheel Measurements and Sizing page.
iiii) The diagram only has a few dimensions on it - more coming soon - This is a work in progress NOW (8th Feb 06).

Choose your rim diameter and choose a width
Rim Diameter (inches):	13 14 10 12 15
Rim Width (inches):	4.5 5 5.5 6 6.5
To calculate 'REAL' width we need:
Rim Edge Width (mm):
OR
Total Rim Width (mm):
Then to calculate mounting point we need:
Backspace (mm):
OR
Offset [+ or −] (mm):
Want to add an offset spacer? :
Spacer (mm):