Originally Posted by
FlyingOnceMore
This is no such thing as 'accurately'. All programs have there own mileage charts, there is no 'standard' distance.
See above for ORD-IAH which should be the same distance no matter if the flight is on CO or UA. While no class bonus distance post correctly, with the class bonus the distance is not the same.
Of course each program has its own chart but even if we assume that A3 had its own chart to, for example ORD-IAH, than it should be consistent no matter which airline you fly on.
If you assume it comes out of United, than it does not fit to United own mileage chart.