Select a distance, either from the drop box or by manual entry. To specify miles, enter the number of miles, a space, and an m, or anything starting with m. To specify kilometres, just enter the number of kilometres.
Enter a time in the format h:mm:ss (you don't need to use colons, anything, including spaces, works fine. 90:00 is the same as 1:30:00. 120:00 is NOT the same as 2:00:00). Click "Get Pace". Equivalent times for the other distances will be displayed along with estimated VO2max and Lactate Threshold running paces and split times for the specified distance.
Enter a mile or kilometre pace in the format (m)m:ss (the same as the time format) and click "Get Time". The corresponding race times, points and all the other stuff will be displayed.
* "VO2max pace" is the estimated pace you could maintain for no more than 10 minutes. "Lactate threshold pace" is the estimated pace you could maintain for no more than 60 minutes. Disclaimer: these values are estimated for the entertainment of running geeks only! Their inclusion here is not intended as an endorsement of their use in any training program. Use at your own risk!
Calculator courtesy of Royal Victoria Marathon.