🏃 Running Pace Calculator — km & Miles, Free & Offline
Instantly calculate your running pace, projected finish time, or distance covered — completely free, no sign-up, and 100% client-side in your browser. Pick what you want to solve: enter distance and time to get your pace, enter pace and distance to get your finish time, or enter pace and time to get your distance. Supports both kilometres and miles, with one-click presets for 5K, 10K, half marathon and full marathon.
About
This running pace calculator covers three core scenarios every runner needs: finding your pace from a known distance and time, projecting a finish time from a target pace and race distance, and estimating how far you ran given a pace and elapsed time. All three modes work in both kilometres and miles with instant unit conversion. Results always show pace in both min/km and min/mi alongside average speed in km/h and mph, so you can share splits with runners on either system. Race-distance preset buttons (5K, 10K, half marathon at 21.0975 km, full marathon at 42.195 km) fill the distance field in one click. All arithmetic runs locally in your browser — no data is uploaded or stored on any server.
How to use
- Choose what to solve for: Pace (from distance + time), Time (from pace + distance), or Distance (from pace + time).
- Toggle between km and mi using the unit button in the top-right corner.
- Enter your values. Use the race preset buttons (5K, 10K, Half, Full) to fill the distance field instantly.
- Click Calculate to see your result highlighted at the top of the results panel.
- Read off pace in both min/km and min/mi plus average speed in km/h and mph — all shown together for easy sharing.
FAQ
- What is running pace and how is it calculated?
- Pace is the time it takes to cover one unit of distance — usually expressed as minutes per kilometre (min/km) or minutes per mile (min/mi). It is calculated by dividing your total running time (in minutes) by the distance covered: Pace = Time / Distance.
- How do I convert pace from min/km to min/mi?
- Multiply your min/km pace by 1.60934 to get min/mi. For example, a 5:00 min/km pace equals approximately 8:03 min/mi. This calculator shows both values automatically in the results.
- What pace do I need to finish a marathon in under 4 hours?
- To finish a marathon (42.195 km) in exactly 4 hours you need a pace of approximately 5:41 min/km (9:09 min/mi). Use this tool: set mode to Pace, click the Full preset, and enter 4h 0m 0s to see the exact figure.
- Does this calculator work offline?
- Yes. Once the page is loaded, all calculations run entirely in your browser with no internet connection required. No data is sent to any server.
- Can I save my inputs for next time?
- Yes. Your inputs (distances, times, pace and unit preference) are automatically saved to your browser's localStorage and restored the next time you open the calculator. Nothing leaves your device.