Definitions
- Moving pace
- Time spent moving per mile or kilometre.
- Elapsed time
- All moving time plus all stopped time since the race start.
- Cumulative distance
- Total distance from the start to the current aid station.
- Stop time
- Time budgeted at the current station after arrival.
Goal mode
Goal mode begins with a desired elapsed finish time. Planned stops are subtracted before pace is calculated because the race clock continues while stopped.
available moving time = goal elapsed time − total planned stopsrequired moving pace = available moving time ÷ race distanceIf planned stops equal or exceed the full goal time, the plan is invalid: there is no positive moving time left to distribute.
Pace mode
Pace mode begins with an expected moving pace. Moving time is calculated for the full race, then planned stops are added to project elapsed finish time.
total moving time = moving pace × race distanceprojected finish = total moving time + total planned stopsCheckpoint arrival and departure
Each station starts where the previous one ended. Segment distance is the current cumulative distance minus the previous cumulative distance.
arrival = prior departure + (segment distance × moving pace)departure = arrival + current station stopThe finish is added automatically. It has an arrival time but no stop or departure delay.
Worked 50-mile calculation
For a 12:00 goal with two five-minute stops, available moving time is 11:50. Dividing 11:50 by 50 miles produces a required moving pace of 14:12 per mile. A station at mile 10 is reached at 2:22 elapsed and departed at 2:27 after its five-minute stop.
Units and rounding
Distances use the international conversion 1 mile = 1.609344 kilometres. When a plan switches units, race distance, station distances, and pace are converted together.
Durations are held in seconds and distances as decimal values. Calculations retain their numerical precision until display. Pace, elapsed time, and clock time are rounded only for presentation, which prevents repeated row-by-row rounding from drifting the finish.
Overnight races
Clock time is derived from the entered local race start and elapsed seconds. The card includes a day number—such as Day 2 or Day 3—whenever an arrival crosses midnight. It does not attempt to infer a time zone or daylight-saving rule for the venue; use the local time shown by the race organizer.
Overall cutoff buffer
cutoff buffer = overall race cutoff − projected finishA positive value is time remaining before the overall cutoff. A negative value is the amount by which the projection exceeds it.
Individual checkpoint cutoffs are not entered in this version. Official rules may require a runner to leave a station before its cutoff, regardless of arrival time, so compare the departure column with the current runner guide.
What the model does not predict
The calculator does not model elevation, grade, technical terrain, altitude, heat, cold, darkness, congestion, navigation, fatigue, nutrition, hydration, injury, or changing pace through the race. A constant average pace is a planning baseline, not a claim that every segment will be run evenly.
Course details and rules can change. Verify distance, station order, closures, mandatory equipment, and cutoff definitions with the organizer before relying on a printed card.
Measurement standard
The mile-to-kilometre conversion comes from the NIST Guide to the SI conversion factors, which lists one international mile as exactly 1,609.344 metres.
All timing formulas are stated on this page and calculated directly from the values entered here. No external data or third-party calculation service is used.