Running Tools
Use the hub below for quick calculations, or open a dedicated calculator page for methodology notes, FAQs, and focused guidance.
Pace
08:02 / mi · 05:00 / km
Speed
7.46 mph · 12 kph
Predicted time
52:07
Target pace
08:23 / mi
Uses the Riegel-style endurance formula with exponent 1.06. Predictions are most useful between similar road race distances and conditions.
Split count
10
Time per split
05:00 per 1 km
Estimated VO2 max
51.3 ml/kg/min
Uses the Cooper 12-minute field-test estimate: VO2 max = (distance in meters - 504.9) / 44.73.
Max HR used
180 bpm
Zone 1
50-60%
90-108 bpm
Zone 2
60-70%
108-126 bpm
Zone 3
70-80%
126-144 bpm
Zone 4
80-90%
144-162 bpm
Zone 5
90-100%
162-180 bpm
Estimated max HR uses 208 - 0.7 x age unless you enter a known max. These are broad percentage zones, not lactate-threshold or lab-derived zones.
Pace, speed, distance conversion, and split calculations are deterministic arithmetic. Race prediction, VO2 max, max heart rate, and training zones are estimates built from common field formulas.
Source basis: Riegel-style race prediction, Cooper 12-minute VO2 max estimate, Tanaka-style max heart rate estimate, and percentage-of-max heart-rate zones. Real results vary with training history, terrain, weather, altitude, fatigue, and measurement quality.