Do the pace math.
Leave the rest to your legs.
Runnin is a free toolbox for runners: calculators, plans and training analysis. Core features work without an account or ads; an account and Strava are optional.
Works on iOS, Android and the web. In Polish and English, in km and miles.
Everything you need before a run
Calculators run locally. If you choose, an optional account saves progress and connects your workouts to Strava.
Pace · distance · time
Enter two values, we compute the third. Shortcuts for 5K, 10K, half and marathon.
Treadmill
km/h to min/km and back, with incline and flat-ground equivalent pace.
Intervals and strides
Rep times to the second: 400 m at 4:00/km = 96 s. Table from 100 m to 3 km.
Split times
Your goal result broken into kilometer splits - with halfway and finish.
Race pacing
Negative, positive or even split - a full pacing plan for race day.
Predictor and HR zones
Race predictions (Riegel formula) and 5 heart rate zones, incl. the Karvonen method.
Why Runnin?
an account and Strava are optional. You decide what gets synchronized.
free, with no ads or in-app purchases.
two languages, metric and imperial units, dark and light mode.
Ready to run faster?
Open Runnin in your browser - it works on your phone too.