How the race pace calculator works
Pace is a division, splits are a plan
Goal time ÷ distance = pace — the easy part. The useful part is the splits table: cumulative times at every mile (or km) that arrive at the goal exactly. Racing by cumulative time survives the surges, the water fumbles, and the hills that make per-mile pace readings lie; the watch's total never argues.
Why even pacing is the right default
Even effort (which on flat courses means even pace) is physiologically optimal: glycogen burns proportional to intensity, and the surges that "bank time" charge interest at the end. On hilly courses, even EFFORT means uneven pace — harder uphills slower, easier downhills quicker — which the split table helps you plan around rather than against.
Adjusting for the course
Add 10–15 seconds per mile for significant hills, 5–10 for hot conditions, and nothing for nervous adrenaline (it will find its own price). The goal time itself should come from a recent race through the equivalency calculator — goals set from training runs alone are where ambitious paces go to die at mile 18.