Pace and speed describe the same run from opposite directions. Pace answers “how long does one kilometer take?” Speed answers “how far do I get in one hour?”
The pair you will actually see
| Pace | Speed |
|---|---|
| 4:00/km (6:26/mile) | 15.0 km/h (9.32 mph) |
| 5:00/km (8:03/mile) | 12.0 km/h (7.46 mph) |
| 6:00/km (9:39/mile) | 10.0 km/h (6.21 mph) |
| 7:00/km (11:16/mile) | 8.57 km/h (5.33 mph) |
| 8:00/km (12:52/mile) | 7.50 km/h (4.66 mph) |
The conversion is division, not a lookup you have to memorize:
- km/h = 60 ÷ minutes per kilometer
- minutes per kilometer = 60 ÷ km/h
A treadmill set to 10.0 is usually 10 km/h, which is 6:00/km, not a 10:00 pace. If the machine is in mph, 6.2 mph is the same neighborhood as 10 km/h. The running speed calculator takes either starting point.
When pace is the better number
Road races are marked in kilometers or miles, and training plans are written as min/km or min/mile. “Run 5:30” means something only after you know the unit. Pace also adds cleanly: five kilometers at 5:30/km is 27:30, which you can check on the 5K pace calculator.
When speed is the better number
Treadmills, some bike computers, and physics problems use speed. Comparing a run with a bike ride is easier in km/h because both sports can share that unit. Pace per kilometer does not transfer to cycling in any useful way.
Do not convert the distance twice
If you already have min/km, multiplying again by 1.609344 gives min/mile. That is a unit change, not a speed change. The pace converter does that step. Doing both the mile conversion and the km/h conversion on the same number, without deciding which one you wanted, is how a 6:00/km run gets copied into a plan as 6:00/mile.
To calculate pace from a finish time first, use the pace calculator, then convert to speed only if you need km/h or mph.