How it works
even split: segment = T · (segmentMeters / distanceMeters); negative split: first half = T/2 · (1 + p/2), second half = T/2 · (1 − p/2)
A pace band distributes your goal time T across the distance. The default even-paced band gives every segment time in proportion to its length, so the cumulative of the final marker lands exactly on T. A negative-split band runs the opening half slightly slower — T/2 · (1 + p/2) — and the closing half exactly as much faster — T/2 · (1 − p/2), where p is your percentage ÷ 100 — and the two halves still add back to T with no drift. Everything is computed in metres and seconds and converted to your unit only at the edge, so the mile and kilometre bands never disagree by rounding, and any partial final segment absorbs the residual so the last cumulative time is exact.
Sources
- Even/negative pacing in endurance racing Even-to-negative pacing yields the best endurance outcomes; positive splits (fading) cost time. The split-distribution model used here keeps the two halves summing exactly to the goal time.
- Endurance basis for steady pacing Riegel, P. S. (1981). “Athletic Records and Human Endurance.” American Scientist 69(3), 285–290 — the endurance basis for steady, controlled pacing that a pace band helps you hold.
- Observed at the elite level Marathon world records are routinely run as even-to-negative splits, with the second half equal to or faster than the first — exactly the distribution a pace band encodes.
FAQ
What is a pace band?
A pace band is a small printed strip listing the cumulative clock time you should hit at each mile or kilometre marker to finish on your goal time. Runners wear it on the wrist or pin it to their bib and glance at it as they pass each marker, so they always know if they are on pace.
How do I print the pace band as a PDF?
Generate the table here, then open your browser’s Print dialog (Ctrl/Cmd-P) and choose “Save as PDF” as the destination — or print straight to paper. There is no separate download or app: the band prints with the rest of the page, so you can save it, share it, or print it small enough to wrap around your wrist. Tip: print at a reduced scale and cut out just the table.
Should I use an even split or a negative split?
Leave the negative-split percentage at 0 for an even-paced band, where every segment targets the same pace — the safest plan for most runners. Set a small 1–3% negative split if you want the band to bank a little time early and run the closing half faster, which is how most personal bests and marathon records are run.
Can I make the band in miles or kilometres?
Yes. Toggle the distance unit between mi and km and the whole band rebuilds — one row per mile or per kilometre, plus a final partial segment if your race is not a whole number of units. The maths is done in metres internally, so the two views agree exactly.
What if my GPS watch shows a different distance than the markers?
Course markers are placed on the official measured line, but a GPS watch usually reads slightly long because you rarely run the exact tangents. Trust the cumulative times on your band at the official markers rather than your watch’s per-mile auto-laps, and treat any small drift as normal.
Does the final cumulative time always equal my goal?
Yes. The split engine builds the band so the cumulative time of the last segment lands exactly on your goal finish time, with any partial final segment absorbing the rounding. The band you wear will always add up to the time you entered.
A pace band is a mathematical pacing plan, not a guarantee of fitness or finish time. Weather, terrain, hills and fuelling all affect the day — adjust on the road as needed. General information for training, not medical or coaching advice.