Settings
Pace /km = time ÷ distance. All calculations run in your browser — nothing is uploaded.
Result
- Pace /km
- —
- Pace /mile
- —
- Speed
- —
- Finish time
- —
Split chart
| Point | Pass time |
|---|
A running and marathon pace calculator. Pick the distance from presets (marathon 42.195km, half 21.0975km, 10K, 5K) or enter your own. In "from time" mode, enter your target time (h:m:s) and it gives pace per km, pace per mile, and speed in both km/h and mph. In "from pace" mode, enter your pace per km (or per mile) and it gives the finish time and speed. You can switch the distance and pace unit between km and miles, and both km/h and mph are always shown. It also builds a split chart (cumulative pass-through time at every km, or at a 2km / 5km / 1-mile interval you choose) that you can print directly on A4 — handy for making a pace band to wear on your wrist or a race-day split sheet. Every calculation runs in your browser; the values you enter are never sent to any server or API.
How to use
- Pick the distance from presets (marathon/half/10K/5K) or enter your own.
- Choose "from time" and enter your target time, or "from pace" and enter your pace per km/mile.
- Read off pace, speed and finish time; print the per-km split chart on A4 with the print button (nothing is sent).
FAQ
Are the time or pace I enter sent anywhere?
No. The pace calculation and the split chart are generated entirely in your browser. The values you enter are never sent to any server or API — everything stays on your device.
What pace do I need to run a marathon in 4 hours?
Choose the "Marathon (42.195km)" preset, switch to "from time" mode and enter 4:00:00. It shows about 5:41 /km (roughly 10.5 km/h). For a sub-3:30 it's about 4:58 /km, and for a sub-3 it's about 4:15 /km.
Can I print the per-km split chart?
Yes. Below the results it builds a split chart with the cumulative pass-through time at each km (you can pick a 1km / 2km / 5km / 1-mile interval), and the "Print chart" button prints it on A4 — useful for a pace band to wear on your wrist.
How is the pace worked out?
Pace per km = time ÷ distance (km). Speed = 3600 ÷ (seconds per km) km/h, and pace per mile = pace per km × 1.609344. In "from pace" mode, finish time = pace per km × distance (km).