Pace Calculator
Calculate your running pace and predict finish times for 5K, 10K, half marathon, and marathon.
Results
What is a Pace Calculator?
A pace calculator turns a finished run — or a race goal — into the two numbers every runner trains by: pace (the minutes it takes to cover one mile or one kilometer) and speed (miles or kilometers per hour). Enter a distance and time to see your pace per kilometer and per mile, or switch tabs and enter a pace plus a distance to get a projected finish time. The running pace calculator above also predicts your 5K, 10K, half marathon, and marathon finish times from any performance you enter, using the Riegel formula.
How to Use This Calculator
- Choose whether you know your distance and time, or your pace and distance.
- Enter the values in the appropriate fields.
- Select the correct units for distance and pace.
- Click Calculate to see your pace and predicted race times.
The Pace and Speed Formulas
Pace and speed are two ways of expressing the same thing:
pace = time ÷ distance
speed = distance ÷ time
- pace — minutes per mile (min/mi) or minutes per kilometer (min/km); a lower number means faster running.
- time — total elapsed time for the run, converted to minutes.
- distance — how far you ran, in miles or kilometers.
- speed — miles per hour (mph) or kilometers per hour (km/h); a higher number means faster running.
Converting between the common units:
- min/mi = min/km × 1.60934 (a mile is longer than a kilometer, so your mile pace is always a larger number).
- min/km = min/mi ÷ 1.60934.
- mph = 60 ÷ min-per-mile. For example, an 8:00 mile equals 60 ÷ 8 = 7.5 mph, or about 12.07 km/h.
- km/h = 60 ÷ min-per-km. A 5:00 kilometer equals exactly 12 km/h.
Worked Examples
Example 1: 5K in 25:00
You run 5 kilometers in 25 minutes. Pace = 25 ÷ 5 = 5:00 per kilometer. Converting: 5 × 1.60934 = 8.0467 minutes, which rounds to 8:03 per mile. Enter these values above and the calculator shows exactly that, plus Riegel predictions based on your 5K: 10K in 52:07, half marathon in 1:55:00, and marathon in 3:59:47.
Example 2: Marathon in 3:45:00
A marathon is 26.2188 miles (42.195 km), and 3:45:00 is 225 minutes. Pace per mile = 225 ÷ 26.2188 = 8.58 minutes, or 8:35 per mile. Pace per kilometer = 225 ÷ 42.195 = 5.33 minutes, or about 5:20 per kilometer. That is the pace you need to hold for just over 26 miles to break 3:45.
Finish Times by Mile Pace
Use this reference table to see what a steady pace produces over the four standard race distances (5K = 3.10686 mi, 10K = 6.21371 mi, half marathon = 13.1094 mi, marathon = 26.2188 mi):
| Pace (per mile) | 5K | 10K | Half Marathon | Marathon |
|---|---|---|---|---|
| 7:00 | 21:45 | 43:30 | 1:31:46 | 3:03:32 |
| 8:00 | 24:51 | 49:43 | 1:44:53 | 3:29:45 |
| 9:00 | 27:58 | 55:55 | 1:57:59 | 3:55:58 |
| 10:00 | 31:04 | 1:02:08 | 2:11:06 | 4:22:11 |
| 11:00 | 34:11 | 1:08:21 | 2:24:12 | 4:48:24 |
| 12:00 | 37:17 | 1:14:34 | 2:37:19 | 5:14:38 |
Pace vs. Speed
Runners talk in pace; treadmills, cyclists, and drivers talk in speed. Pace is time per unit of distance (8:00 per mile), so it improves as the number gets smaller. Speed is distance per unit of time (7.5 mph), so it improves as the number gets larger. Because they are reciprocals, converting is easy: divide 60 by your minutes-per-mile pace to get mph. Our speed calculator handles conversions between mph, km/h, m/s, and knots if you need other units.
Negative Splits: Racing Smart
A negative split means running the second half of a race faster than the first half. It is the strategy behind nearly every distance world record: start slightly slower than goal pace while your body warms up, then press in the second half instead of fading after an aggressive start. For example, targeting a 1:58 half marathon (9:00 per mile), you might run the first half of the course in about 60:00 and the second in about 57:59, finishing in 1:57:59 feeling strong rather than surviving a collapse. Even pacing is a fine goal too — the table above shows what perfectly even splits produce.
Treadmill Pace Conversion
Most treadmills display speed in mph, not pace. To set the belt to match your training pace, use mph = 60 ÷ min-per-mile. Common settings: 6.0 mph = 10:00 per mile, 6.5 mph = 9:14, 7.0 mph = 8:34, 7.5 mph = 8:00, and 8.0 mph = 7:30. Because treadmill running lacks wind resistance and the belt assists leg turnover, many coaches suggest setting the incline to 1% to approximate outdoor effort at the same pace. To estimate the energy cost of a treadmill session, try our calories burned calculator.
Frequently Asked Questions
What is the Riegel formula?
The Riegel formula predicts race times for different distances based on a known performance: T2 = T1 × (D2/D1)^1.06. It assumes similar training and conditions across distances.
How accurate are race predictions?
Predictions are most accurate when moving between similar distances (e.g., 10K to half marathon). Jumping from 5K to marathon involves endurance factors the formula may underestimate.
How do I calculate my running pace?
Divide your total time by the distance covered. For example, a 5K (5 km) finished in 25:00 gives 25 ÷ 5 = 5:00 per kilometer, which converts to about 8:03 per mile. Enter any distance and time above to get both instantly.
How do I convert pace from min/km to min/mi?
Multiply your min/km pace by 1.60934 to get min/mi. This calculator handles the conversion automatically when you switch units.
How do I convert pace to miles per hour?
Divide 60 by your minutes-per-mile pace: mph = 60 ÷ pace. An 8:00 mile equals 60 ÷ 8 = 7.5 mph. To convert the other way, divide 60 by the speed: 7.5 mph is 60 ÷ 7.5 = 8:00 per mile.
What is a negative split?
A negative split means running the second half of a race faster than the first half. It is the pacing strategy behind most distance world records: start conservatively, then speed up once you are fully warmed up, instead of slowing down after a too-fast start.
What is a good marathon pace?
Marathon pace is typically 15–30 seconds per mile slower than half-marathon pace for recreational runners. Elite runners maintain paces under 5:00 per mile.