Running calculators for pace, race times and training
Use these free running calculators to work out your pace, estimate race finish times, plan race splits, convert treadmill speed and prepare for your next running goal. Whether you are starting with a 5K or training for a marathon, these tools turn your distance and time into practical numbers. Try the running pace calculator, browse the running goal guides or build a general framework with the training plan builder.
Your running calculator hub
Use these tools to turn a recent run into useful numbers, plan a realistic target, understand your training and prepare for race day. Calculators provide estimates, not guarantees: your fitness, terrain, weather, health, elevation and race-day conditions all matter.
Pace calculator
Calculate minutes per kilometre or mile from your distance and finish time.
Race time predictor
Estimate a possible finish time at another distance from a recent result.
Race split planner
Plan target splits and cumulative times for an even-paced effort.
Treadmill converter
Convert outdoor pace into approximate treadmill speed.
Speed calculator
Compare pace and average speed.
Heart-rate zones
Estimate zones using a maximum heart-rate value.
Cadence calculator
Measure steps per minute during a run.
Long-run fuelling planner
Estimate total carbohydrate from your planned hourly intake.
Training pace calculator
Estimate easy, steady, tempo and interval pace ranges from a recent 5K.
Performance benchmark
Compare a result with a reference time you choose.
Age-grade calculator
Calculate a percentage from your time and a matching age-grade standard.
Triathlon & Ironman calculator
Combine swim, bike, run and transition times.
Race countdown
Count the days until your event.
Parkrun / 5K guide
Use your recent performance to set a sensible 5K goal.
Elevation-adjusted pace guide
Understand why hills and terrain change effort and speed.
How to use the calculators well
Use a recent, representative result and compare like with like. A road 5K prediction will not perfectly forecast a hilly trail race. Recalculate as your fitness develops, and use training trends alongside how you feel rather than chasing a number every session.
Frequently asked questions
Are the results guaranteed?
No. Predictions and conversions are estimates based on the inputs and assumptions. They cannot account for every individual or course condition.
Should I train to the predicted pace?
Use a prediction as one reference point. Easy runs should remain comfortable, and training targets should reflect your experience, recovery and current fitness.
Can I use kilometres or miles?
Choose the units offered by each calculator and keep units consistent when entering distances and pace.
Why does trail pace differ from road pace?
Elevation, surface, technical footing, mud, weather and stops can have a major effect. Trail efforts are often better managed by effort than by road pace alone.