Runners’ lives are complicated by the intersection of metric and English race distances and a Babylonian-era base-60 time system. Use these methods to simplify calculating your average race pace.
Take your race time and convert it to total seconds. How? Multiply the number of hours (if any) by 3,600. Multiply minutes by 60. Add these two figures and then add the race-time seconds to that total. Examples: A marathon run in 3:47:23 equals 10,800 (3 X 3,600) + 2,820 (47 X 60) + 23 = 13,643 seconds. A 5-mile race run in 33:15 = 1,980 (33 X 60) + 15 = 1,995 seconds.
Divide the total number of seconds by the distance for the race in miles. If the race is a metric distance, you must find the mile equivalent for the distance. (See the chart below.) Examples from above: Marathon pace = 13,643 seconds/26.22 miles = 520.3 seconds per mile. Five-mile pace = 1,995 seconds/5 miles = 399 seconds per mile.
Convert the seconds per mile pace to minutes and seconds per mile by dividing by 60 and noting the remainder seconds. For the marathon pace: 520.3 seconds per mile/60 = 8 minutes 40.3 seconds per mile. For the 5-mile pace: 399 seconds per mile / 60 = 6 minutes 39 seconds per mile.
Take your race time and convert it to total seconds. How? Multiply the number of hours (if any) by 3,600. Multiply minutes by 60. Add these two figures and then add the race-time seconds to that total. Examples: A marathon run in 3:47:23 equals 10,800 (3 X 3,600) + 2,820 (47 X 60) + 23 = 13,643 seconds. An 8K race run in 33:15 = 1980 (33 X 60) + 15 = 1,995 seconds.
Divide the total number of seconds by the distance for the race in kilometers. If the race is an English distance, you must find the metric equivalent for the distance. (See the chart below.) Examples from above: Marathon pace = 13,643 seconds/42.2 kilometers = 323.3 seconds per kilometer. 8K pace = 1995 seconds/8 kilometers = 249.4 seconds per kilometer.
Convert the seconds per kilometer pace to minutes and seconds per kilometer by dividing by 60 and noting the remainder seconds. For the marathon pace: 323.3 seconds per kilometer/60 = 5 minutes 23.3 seconds per kilometer. For the 8K pace: 249.4 seconds per kilometer/60 = 4 minutes 9.4 seconds per kilometer.
Distance Equivalents for Common Race Distances
| MILES | KILOMETERS | KILOMETERS | MILES |
| 1 | 1.609 | 1 | .6214 |
| 5 | 8.045 | 5 | 3.107 |
| 8 | 12.872 | 8 | 4.971 |
| 10 | 16.090 | 10 | 6.214 |
| 13.109 | 21.095 | 15 | 9.321 |
| 15 | 24.135 | 20 | 12.427 |
| 20 | 32.180 | Half-Marathon (21.095) | 13.095 |
| 26.219 | 42.190 | Marathon (42.190) | 26.219 |
Divide your pace in miles per hour into 60 to get pace in minutes. Convert fractional part to seconds.
Example: You are running on a treadmill and the pace is given as 8.9 mph. Divide 60 by 8.9 to yield 6.742 minutes per mile. Multiply .742 by 60 to yield 44 seconds. Your pace is 6 minutes 44 seconds per mile.
Change seconds to decimal part of a minute and add to minutes. Then divide 60 by total.
The key run workout is to be run at 8:45 pace. Your treadmill displays only miles per hour. Divide 45 seconds by 60 seconds to yield .75. Add to 8 to get 8.75. Divide 60 by 8.75 to yield 6.9 mph.
Divide your pace in kilometers per hour into 60 to get pace in minutes. Convert fractional part to seconds.
Example: You are running on a treadmill and the pace is given as 14.5 kph. Divide 60 by 14.5 to yield 4.14 minutes per kilometer. Multiply .14 by 60 to yield 8 seconds. Your pace is 4 minutes 8 seconds per kilometer.
Change seconds to decimal part of a minute and add to minutes. Then divide 60 by total.
The key run workout is to be run at 5:23 pace. Your treadmill displays only kilometers per hour. Divide 23 seconds by 60 seconds to yield .383. Add to 5 to get 5.383. Divide 60 by 5.383 to yield 11.1 kph.