Which pace calculator do you need?
The pace calculator answers the everyday question: you ran a distance in a time, so what was your pace? It also works backwards, giving a finish time from a pace or the distance covered in a timed run. If you only need to switch units, the pace converter turns minutes per mile into minutes per kilometre, mph, km/h and 400 m lap times in one step.
Planning a race is a different job. The split calculator breaks any goal into splits of any length and can tilt them into a negative split, where the second half is faster. The race time predictor takes one recent result and estimates every other distance with two published models side by side, so you can see how much they agree.
Hilly route? The grade-adjusted pace calculator converts a pace on a slope to the flat-ground pace with the same energy cost, from Minetti and colleagues' 2002 measurements.
Running a hilly race? The course pace planner reads the course GPX and gives even-effort splits. Unsure how far a race is? See race distances in miles and km.