Any distance, one required pace
Not every race is a standard distance — a 10 mile road race, a 30 km trail race and a 50 km ultra all need the same division. Enter the distance in kilometres or miles, plus the goal time, and the result is the pace that produces it, along with the speed in km/h for bike-leg or treadmill comparisons.
Checkpoints every 5 km
Split tables are easier to use at 5 km intervals than at every kilometre, because that is how most courses are marked and how pacers call the time. The table gives elapsed time at each marker, so you can compare it with the clock rather than doing mental arithmetic while running.
The plan versus the day
This is a target, not a forecast. Wind, heat and elevation will move the achievable pace by a few percent, and the first 5 km is usually slower than average on a crowded course. Use the checkpoint as a trend: two consecutive markers on target is meaningful, one marker is noise.
Frequently Asked Questions
Can I enter a distance in miles for a metric race?
Yes. The pace is calculated in the unit you choose and both units are shown in the result.
What is a 2% negative split?
Running the second half 2% faster than the first. The result shows the first-half time you would need, which is 1% slower than the average.
Does this work for trail races?
The arithmetic does, but trail pace depends on elevation and terrain. Add 10–20% for technical ground and treat the checkpoints as optimistic.
Related tools
Privacy & your data
SwimRunPace calculates everything in your browser. Distances, times and body weights are never uploaded — there is no account, no server-side record and no training history stored between visits.