Estimate a finish for a repeating run/walk plan or solve the run or walk pace needed for a target time.
How the Run Walk Interval Calculator Works
The calculator simulates alternating segments in their real order rather than using only a weighted average. That makes the count and final partial segment explicit.
Each full run or walk duration is converted to distance from its pace. If the next segment would cross the finish, only the exact time needed for the remaining distance is added.
Run/Walk Segment Simulation
Formula: segment distance = segment duration / pace seconds per meter
Reverse modes repeatedly simulate the plan while bisecting the unknown pace until the goal time is matched within the supported range.
Choosing the Right Inputs
Enter the event distance, visible pace fields, and both interval durations. Every mode starts with a run interval; reverse modes add a finish-time goal.
| Segment | Duration | Distance | Share of cycle time | Cumulative cycle distance |
|---|---|---|---|---|
| Run | 4:00 | 800 m | 80% | 800 m |
| Walk | 1:00 | 100 m | 20% | 900 m |
| Full cycle | 5:00 | 900 m | 100% | 900 m |
Understanding Your Results
The finish or required pace appears first, followed by average pace, component paces, full segment counts, final partial segment, total run/walk time, and cycle distance.
A final partial run or walk is expected when the course distance is not an exact multiple of one full cycle.
Worked Example
At 5:00/km for four minutes and 10:00/km for one minute, one cycle covers 900 meters. A 5K ends during a partial run and takes about 27:30.
Common Mistakes
Do not assume an integer number of cycles, place the walk segment first, or compare pace numbers without converting their kilometer or mile basis.
Assumptions and Limitations
The model assumes each run and walk segment holds the entered pace and ignores acceleration, terrain, stops, fatigue, weather, and course measurement error.
Sources
Jeff Galloway. The Run-Walk-Run Method. Third edition.
Kuno Hottenrott and colleagues. Does a Run/Walk Strategy Decrease Cardiac Stress During a Marathon in Non-Elite Runners? Journal of Science and Medicine in Sport, 2016.