Running Pace Calculator
Calculate running pace per kilometer or mile, and speed, from distance and time.
How it works
Pace and speed describe the same underlying effort from two different angles: pace is time per unit distance (minutes per km or mile) — the number runners typically think in — while speed is distance per unit time (km/h or mph), more familiar from driving.
Pace is calculated as total time divided by distance: running 5 km in 25 minutes gives a pace of 25 ÷ 5 = 5 minutes per km. Speed is the inverse relationship, distance divided by time: 5 km ÷ (25/60 hours) = 12 km/h.
Converting between per-kilometer and per-mile pace uses the same 1.609344 factor as any other km-to-mile conversion: a 5:00/km pace converts to roughly 8:03/mile (5:00 × 1.609344 ≈ 8:03), since each mile covers more ground than a kilometer and therefore takes longer at the same pace.
This calculator works equally well in reverse for race planning: enter your goal distance and target finish time, and it shows the exact pace per km or mile you'll need to hold consistently to hit that goal — useful for pacing strategy before a race, or for checking whether a goal time is realistic given your current training pace.
Pace naturally varies by distance and effort level: a runner's fastest sustainable pace for a 5K is typically noticeably quicker than their marathon pace, since shorter races allow for higher intensity that can't be sustained over a much longer distance — comparing paces across very different race distances isn't a direct apples-to-apples comparison.
Splits — the pace for individual segments of a longer run or race — are a related concept: a runner might plan "even splits" (holding the same pace throughout) or a "negative split" strategy (running the second half faster than the first), both of which use this same pace-per-distance calculation applied to smaller chunks of the full distance.
Training plans often prescribe target paces for different workout types — easy runs at a conversational pace, tempo runs at a comfortably hard pace, and interval workouts at a much faster pace — and this calculator's reverse mode (finding pace from a goal time and distance) is equally useful for translating those prescribed paces into concrete per-km or per-mile targets to watch on a watch or phone during a workout.
How do I use this to plan a race?
Enter your goal distance and target finish time to see the pace per km/mile you'll need to hold.
How do I convert a per-km pace to a per-mile pace?
Multiply the per-km pace by 1.609344 (the same km-to-mile conversion factor used for distance) — a 5:00/km pace converts to roughly 8:03/mile.
What's the difference between pace and speed?
Pace is time per unit distance (min/km), most familiar to runners; speed is distance per unit time (km/h), most familiar from driving — they describe the same effort, just expressed in inverse units.
Why is my 5K pace faster than my marathon pace?
Shorter distances allow for a higher sustainable intensity, since there's less time for fatigue to accumulate — pace naturally slows as race distance increases for most runners.
What are even splits and negative splits?
Even splits mean holding the same pace throughout a run; a negative split means running the second half faster than the first — both are pacing strategies runners use, calculated using this same pace-per-segment logic.
How do I calculate my finish time from a target pace?
Multiply your target pace (time per km or mile) by the total race distance to get the projected finish time.
Does this calculator work for walking pace too, not just running?
Yes — the math is identical regardless of the activity; enter your actual distance and time to get pace and speed for walking, running, or any similar activity.
Why do race results sometimes show pace instead of total time?
Pace normalizes performance across different distances, making it easier to compare effort or set consistent training targets independent of how long or short a specific run was.
What's a tempo run, and what pace should it be run at?
A tempo run is a sustained effort at a "comfortably hard" pace, typically somewhere between easy training pace and race pace — this calculator can convert a prescribed tempo pace into a concrete per-km or per-mile target.
Why do training plans specify different paces for different workouts?
Different paces target different physiological adaptations — easy runs build aerobic base with low fatigue, while faster interval work builds speed and lactate tolerance; matching effort to purpose is central to structured training.