A fast, private pace calculator for runners and cyclists
Whether you are training for your first 5K or trying to qualify for a major marathon, understanding your pace is essential. This pace calculator helps you figure out exactly how fast you need to run to hit your target time, how long a run will take at a specific pace, or how far you traveled during a timed workout.
Because this tool runs entirely locally in your web browser, your inputs are never uploaded to a server. The calculations happen instantly on your device, making it a fast and reliable companion for your training plan.
How the running pace calculator works
The relationship between distance, time, and pace is a simple mathematical formula. If you know two of these variables, you can always find the third. This tool lets you select which variable you want to solve for:
- Solve for Pace: Enter your total distance and finish time to find your average pace. This is perfect if you just finished a run and want to know your average speed, or if you are using it as a marathon pace calculator to determine the exact split times needed to hit a goal finish time.
- Solve for Time: Enter your distance and target pace to calculate your total finish time. This acts as a race time calculator, helping you predict when you will cross the finish line if you maintain a steady effort.
- Solve for Distance: Enter your total running time and average pace to find out how far you went. This is useful if you run for a set amount of time (like a 45-minute tempo run) and want to log the exact distance in your training journal.
Quick presets and unit conversions
Runners often think in specific race distances and distinct units depending on where they live. To make planning easier, this tool includes built-in presets for the most common official race distances: 5K (5 km), 10K (10 km), Half Marathon (21.0975 km), and Marathon (42.195 km). Clicking one of these buttons instantly fills in the exact decimal distance, saving you from looking it up.
Additionally, the tool doubles as a min per km calculator and unit converter. Whether you prefer kilometers or miles, you can toggle the primary unit at the top. When your results are generated, the calculator automatically displays the equivalent metrics in the alternative unit. For example, if you calculate a pace in minutes per kilometer, the results panel will also show your exact minutes per mile, your total distance in miles, and your overall speed in kilometers per hour (km/h). If you need to do standalone conversions later, you can use our Kilometers to Miles Converter.
Pace vs. Speed: What is the difference?
While both pace and speed measure how fast you are moving, they are expressed differently:
- Pace is expressed as time per unit of distance (e.g., 5:30 min/km or 8:45 min/mi). It answers the question: How long does it take me to cover one kilometer or mile? Runners and swimmers almost exclusively use pace because it makes it easy to calculate split times during a race.
- Speed is expressed as distance per unit of time (e.g., 12 km/h or 7.5 mph). It answers the question: How far will I travel in one hour? Cyclists and treadmills often use speed.
This calculator bridges the gap by providing both. Whenever you calculate a result, your overall speed (in km/h or mph) is displayed alongside your pace, making it easy to set the correct speed on a gym treadmill to match your outdoor training pace.
Tips for race planning
When using a race time calculator to plan your event, keep in mind that the calculated pace is an average. In a real-world race, your pace will fluctuate due to hills, fatigue, and course crowding.
Many runners aim for "even splits" (running every kilometer at the exact same pace) or "negative splits" (running the second half of the race slightly faster than the first). If your marathon goal requires an average pace of 5:00 min/km, you might plan to start at 5:10 min/km to warm up, and gradually accelerate.
If you are calculating complex interval workouts or adding up multiple split times, our Time Calculator can help you add and subtract hours, minutes, and seconds. And if you are tracking your energy expenditure during these long runs, check out the Calorie Calculator to estimate your daily needs.