Pace Calculator
Pace, time, distance — know any two, get the third instantly. Works in kilometers and miles.
Run your numbers
Quick picks: 5K = 5 km · 10K = 10 km · half marathon = 21.0975 km · marathon = 42.195 km
How to Use the Pace Calculator
Pick what you want to find, enter the two things you know, and the answer appears instantly:
- Find my pace — ran a distance in a known time? Get your average pace per km and per mile, plus speed.
- Predict finish time — targeting a pace for a race? See your predicted finish time for any distance.
- Find my distance — have 45 minutes and a comfortable pace? See how far you'll get.
All three modes work in kilometers or miles — switch units freely; conversions use the exact 1 mile = 1.609344 km. You can even type formulas into the boxes (like 21.0975 for a half marathon) or reuse your saved numbers.
The Pace Formula
Pace is simply time divided by distance — the inverse of speed. Three formulas, one relationship:
To convert between units: min/mile = min/km × 1.60934. Speed is the flip side: km/h = 60 ÷ pace (min/km).
Worked Example: 10K in 55 Minutes
Profile: 10 km run finished in 55:00
Step 1 — pace: 55 min ÷ 10 km = 5.5 min/km = 5:30 /km.
Step 2 — per mile: 5.5 × 1.60934 = 8.85 min/mile = 8:51 /mi.
Step 3 — speed: 60 ÷ 5.5 = 10.9 km/h (6.8 mph).
Want a sub-50 10K? You'd need 50 ÷ 10 = 5:00 /km — flip to "Predict finish time" mode and experiment.
Pace Chart Highlights
What do common paces mean in practice? A few reference points (per km):
| Pace (/km) | 5K time | 10K time | Marathon | Feels like |
|---|---|---|---|---|
| 4:00 | 20:00 | 40:00 | 2:49 | Fast club runner |
| 5:00 | 25:00 | 50:00 | 3:31 | Solid recreational |
| 5:30 | 27:30 | 55:00 | 3:52 | Fit beginner |
| 6:30 | 32:30 | 1:05:00 | 4:35 | Comfortable jog |
| 7:30 | 37:30 | 1:15:00 | 5:18 | Easy / run-walk |
Marathon equivalents assume you could hold the pace — in reality, pace fades with distance, so treat the long predictions as optimistic.
Race Day Strategy Tips
- Start slower than target. The classic beginner error is banking time early — it always costs double late. Run the first 10% slightly slower than goal pace.
- Negative splits win. Aim to run the second half marginally faster than the first; it's both faster overall and far more enjoyable.
- Know the course. Hills, heat, and wind change everything — adjust goal pace by effort, not by the watch alone.
- Practice your fueling. Nothing new on race day: rehearse gels, water stops, and shoes on long runs.
- Trust your training. The hay is in the barn — the last week is about rest, sleep, and arriving fresh, not squeezing in one more hard session.
My saved numbers reuse them in any calculator
Save a number once — like your rent or hourly rate — then just type its name instead of the number, in any calculator here. You can also type formulas like 5000 * 1.1 right into any box.
Saved only in this browser — nothing is sent to us.
Frequently Asked Questions
How do you calculate running pace?
Divide your total time by the distance: pace = time ÷ distance. Run 10 km in 55 minutes and your pace is 55 ÷ 10 = 5:30 per km. To predict a finish time, multiply pace × distance instead.
What is a good 5K pace?
It depends on your level. Beginners often run 7:00–8:30/km (35–42 min 5K); fit recreational runners hit 5:00–6:00/km (25–30 min); club runners go sub-20 minutes (under 4:00/km). The best pace is one you can sustain — compare against your own history, not others'.
How do I convert min/km to min/mile?
Multiply by 1.60934: 5:30/km × 1.60934 ≈ 8:51/mile. To go the other way, divide min/mile by 1.60934. This calculator converts automatically when you switch units.
What pace should I target for a marathon?
A realistic marathon pace is usually 15–30 seconds per km slower than your half-marathon pace. Use the "Predict finish time" mode with an honest pace — then check it against a recent long run. Most first-timers do best starting conservatively.
How can I improve my running pace?
Build weekly mileage gradually (no more than ~10% per week), add one interval or tempo session weekly, do most running easy (Zone 2), strength-train twice a week, and sleep well. Consistency over months beats any single hard workout.