hedgehog It’s a pretty straightforward calculation for most horses
take the 1.50 Goodwood all older horses , calling the wind 114 on race card, carrying 9-12 so 2 lb below 10st so his master rating would be 114-2=112. Click into horses form and you will see the 112 comes from latest run
This calculation is the same if the horses in the race are all 2yo or 3yo.
The only problem occurs when WFA is a factor.
If 3yo are running against older horses for instance if you look at 8.00 newmarket
Dion Baker is a 4yo so calculated as normal 78 on the race card carrying 9-10 so 4lbs less than 10st . 78 - 4 = 74 master
but if we look at Panning For Gold he is 79 on the racecard carrying 9-4 so should be 79 - 10 = 69, but because he is receiving WFA being a 3yo against older horses then you must add on the WFA value for this race.
This is the time consuming part you would have to source the Racing Post scale of WFA as it differs from the official.
From the RP WFA table attached for 3yo’s in this race is 6lb
so the master rating for Panning For Gold would be 79 - 10 + 6 = 75, click on the horses record and you can see that this is the case.
Hope this helps .
