Race Split Planner
Enter a race distance, goal total time, and checkpoint percentage to calculate your required pace and checkpoint timing.
A QUICK WALKTHROUGH
How to use this tool
- Enter the race distance in kilometers and goal time in minutes.
- Enter a checkpoint percentage from the start.
- Review the required min/km pace, checkpoint distance, and elapsed time.
Formulas
Required pace in minutes per kilometer = goal minutes / distance kilometers. Checkpoint distance = distance kilometers × checkpoint percent / 100. Checkpoint elapsed minutes = goal minutes × checkpoint percent / 100.
An even-pace planning guide
This tool describes an ideal even-pace plan. It is not a guarantee: terrain, weather, fatigue, crowds, stops, and race conditions can change your actual pace and split times.
Local calculation
Your inputs stay in your browser. The tool does not predict performance or replace coaching or medical advice.
Input bounds and report
Distance and goal minutes must be positive; checkpoint is 0–100%. Only the selected checkpoint is calculated. Use finite decimal inputs with at most 15 significant digits and magnitude at most 9,007,199,254,740,991. Arithmetic that loses a nonzero value or cannot distinguish required terms is rejected. Copy and TXT contain the successful raw/parsed input snapshot, units, formulas and all unrounded browser-number results; editing clears it.
GOOD TO KNOW
Common questions
Does the planner guarantee my race result?
No. It gives an ideal even-pace target; real conditions and effort may change your actual splits.
What does the checkpoint percentage mean?
It is the portion of the race measured from the start. For example, 50% of a 10 km race is 5 km.
Are my values uploaded?
No. Calculations run locally in your browser.