Calculate your running pace, finish time, or distance. Supports 5K, 10K, half marathon, and marathon with race time predictions.
Whether you are training for your first 5K or targeting a marathon PR, our running pace calculator helps you plan every race and training run. Use Pace mode to analyze past runs, Finish Time mode to set race goals, or Distance mode to plan time-based workouts. The race prediction table gives instant estimates for 5K, 10K, half marathon, and marathon based on your current pace — great for setting realistic race goals. All calculations run entirely in your browser — your data never leaves your device.
Running pace is the time it takes to cover one unit of distance — typically expressed as minutes per mile (min/mi) or minutes per kilometer (min/km). It is the inverse of speed: a faster runner has a lower pace number (fewer minutes per mile) and a higher speed number (more miles per hour).
The three fundamental relationships:
Our calculator supports all three modes — enter any two values to calculate the third. It also converts automatically between min/mi, min/km, mph, and kph.
Understanding training pace zones helps structure runs for different fitness objectives:
Elevation affects pace significantly. A rule of thumb: add approximately 90 seconds per mile for every 100 feet per mile of elevation gain. Running on trail surfaces adds a further 10–20% to equivalent effort pace. Our calculator works with flat-course pace — factor in terrain when setting realistic training targets.
Emma wants to finish a half marathon (13.1 miles) in under 2 hours. What pace does she need?
Required pace = 120 minutes ÷ 13.1 miles = 9:09 per mile (or 5:41 per km)
To build safely to this race pace, Emma's training should include:
Using our pace calculator, Emma can also see predicted finish times for other distances at her current fitness: if she runs a 9:09/mi half marathon, the race predictor estimates a 5K of approximately 25:30, a 10K of around 53:00, and a full marathon of roughly 4:10 using standard performance conversion models.
Fitness level and aerobic base: Aerobic capacity (VO2max) is the primary determinant of running performance. Higher VO2max means a faster sustainable pace at any given effort level. Consistent training over months and years raises VO2max and improves running economy — how efficiently you use oxygen at a given pace.
Terrain: Soft surfaces (trails, grass) absorb more energy with each footstrike, slowing pace by 10–20% compared to road or track at equivalent effort. Hills add significant time — a 5% grade at 5:00/km effort feels like running 4:15/km on flat terrain in terms of cardiovascular demand.
Weather conditions: Heat and humidity are the biggest environmental pace disruptors. Performance drops measurably above 55°F (13°C) for competitive runners and more significantly above 70°F (21°C). A common adjustment is to add 30 seconds per mile for every 10°F above 60°F on race day.
Race distance: Nobody can sustain 5K pace for a marathon. As race distance increases, sustainable pace slows in a predictable pattern. World-class athletes run a marathon approximately 10–15% slower than their half marathon pace. Recreational runners typically slow 15–25% from half to full marathon.
Heart rate zones: Pace is a proxy for effort, but heart rate directly measures cardiovascular load. Two runners at the same pace may be at very different effort levels depending on their fitness. Over time, tracking both pace and heart rate reveals fitness improvements: the same pace becomes easier (lower heart rate) as aerobic capacity improves.
A good beginner running pace is whatever allows you to hold a conversation while running — typically 12–15 minutes per mile (7:30–9:20 per km). Speed matters much less than consistency for beginners. Focus on running for time rather than distance, and gradually build your weekly mileage before worrying about pace.
Pace per mile is your total running time divided by the distance in miles. For example, running 3.1 miles (5K) in 30 minutes gives a pace of 9:41 per mile. Our running pace calculator does this instantly — just enter your distance and time to see your pace in min/mile, min/km, mph, and kph.
To finish a marathon in under 4 hours, you need to average 9:09 per mile (5:41 per km). The full marathon distance is 26.2188 miles, so 4 hours ÷ 26.2188 = 9.16 minutes per mile. Allow some cushion — target 9:00 per mile to account for fatigue and course variation.
To run faster, include interval training (short fast bursts with recovery), tempo runs (sustained effort at threshold pace), and weekly easy runs to build aerobic base. Strength training — particularly legs and core — improves running economy. Most runners benefit from running 4–5 days per week with 80% of miles at easy effort.
Pace measures time per unit of distance (e.g., 9:00 per mile), while speed measures distance per unit of time (e.g., 6.7 mph). Runners typically use pace, while cyclists and other sports tend to use speed. A faster runner has a lower pace number and a higher speed number. Our pace calculator shows both.