Running tools
Fast, free calculators for planning 5K training and races. Everything runs in your browser. No sign-up, and nothing you type is sent anywhere.
5K goal calculator
Current and goal 5K → paces, weeks-to-goal range and a plan preview.
OpenRunning pace calculator
Pace from time, or time from pace.
OpenRace time predictor
Mile to marathon, Riegel formula.
OpenSplit calculator
Even and negative splits per km or mile.
OpenTraining pace calculator
Easy, tempo, interval and repetition paces from your 5K.
OpenTreadmill pace converter
Mph or km/h to min/mile and min/km.
OpenKm to mile pace converter
Min/km ↔ min/mile.
OpenPace charts
Prefer a table you can print or save? See the pace charts: every 5K time from 15:00 to 45:00, mile pace to race times, and goal charts for sub-20, sub-25 and sub-30.
We left out an age-grading calculator on purpose. Accurate age grading needs the official World Masters Athletics factor tables, and we'd rather not publish an approximation that looks precise but isn't.