The conformity is the ratio between radius of curvature of a race and the ball diameter. For geometric reasons, the value has to be larger than 0.5. The values used for the calculation of tables in ISO 281 are fi=fe=0.52 for radial ball bearings and fi=fe=0.535 for thrust ball bearings as stated in ( ISO/TR 1281-1, 2008).
Using the -button behind the input field, the conformity can be calculated from a given radius. Ensure that you input the correct roller and pitch diameter before.