Laktic Pace Calculator turns an athlete's race PR into threshold training paces and adjusts them for heat and humidity using live local weather.
Enter a 5000m, 3200m, 3000m, 1600m, mile, or 1500m PR and the app computes the Track and Road Performance training zones: Easy, Long Run, Steady, and the three threshold zones LT1, Sub-T, and LT2. Get today's temperature and dew point for your location, search a city or ZIP, or type the numbers yourself, and every pace is slowed by the heat penalty.
The adjustment is scaled by rep length. Short threshold reps with recovery build less heat load than continuous running, so 1-3 minute reps take half the penalty, 4-6 minute reps three-quarters, and 7-10 minute reps and continuous runs the full amount. Within each threshold zone, short reps sit at the fast end of the range, medium reps in the middle, and long reps at the slow end.
Every pace shows the per-mile range and the seconds-per-400 m split, so it goes straight to the track.
FOR COACHES
Keep a roster of athletes on your phone and build a workout board for today's conditions. Pick a zone and rep length and see every athlete's heat-adjusted range, fastest first, filtered by group. Export the roster as a file, import one from an assistant coach, or copy a share link that opens the same roster in the web version.
PRIVACY
Your location is used only on your device to fetch weather from Open-Meteo. Athlete names and PRs stay on your device unless you export them. There are no accounts, no tracking, and no ads.
Training guidance, not medical advice. Use judgment in extreme conditions.
Pace engine: Track and Road Performance. Weather data by Open-Meteo.
Threshold paces with automatic heat adjustments.