How it works
race pace = goal time ÷ distance
Divide the goal time by the distance: a 1:45:00 half marathon is 105 minutes across 13.1 miles, which demands about 8:01 per mile. The tool runs this in meters and seconds under the hood and converts only for display, so the per-mile and per-km figures describe one identical speed rather than two independently rounded cousins. The 400 m line scales the same pace to a single track lap — useful for goal-pace repeats — and the checkpoint table spreads the goal evenly across every full mile or kilometer, closing exactly on your target at the final row.
Sources
- Definition of pace Average speed = distance ÷ time (kinematics); pace is its inverse, expressed as time per unit distance.
- Even pacing and race outcomes Riegel, P. S. (1981). “Athletic Records and Human Endurance.” American Scientist 69(3), 285–290 — steady effort is the efficient default for distance racing.
- Track lap standard World Athletics — a standard outdoor track lap is 400 m.
FAQ
What race distances can I enter?
Anything above zero — the distance field is a free number with a mi/km toggle, plus presets for the 5K (3.1), 10K (6.2), and half (13.1). That makes this the fallback tool when your event is an 8K, a 10-miler, a 30K tune-up, or an ultra leg no dedicated calculator covers.
How is the required pace worked out?
Goal time divided by distance — nothing more exotic. The value the tool adds is packaging: one answer expressed per mile, per kilometer, as a speed, and as a 400 m lap, plus a split-by-split table that turns the division into something you can follow mid-race.
What is the 400 m lap time for?
Track workouts at goal pace. If your target computes to 8:01 per mile, one lap of a standard outdoor track should take a hair under two minutes — the result gives the exact figure, so you can rehearse race rhythm in 400 m doses months before the start line.
Should I actually run even checkpoints on race day?
The table assumes even effort because that wastes the least energy on most courses, and it is the easiest plan to monitor. Plenty of strong races close with a slightly quicker second half, though — if that suits you, build the plan in the negative split calculator and keep this table as your even-effort baseline.
Why do the mile and kilometer paces look so different?
Because the units differ by 61% in length — one mile is 1.609344 km — while the underlying speed is a single number. An 8:01 mile pace and a 4:59 km pace are the same running; multiplying a per-mile figure by 0.6214 gives the metric view whenever you need it by hand.
Is required race pace the pace I should train at?
Mostly no. Race pace is a race-day output; day-to-day running should sit comfortably slower, with only targeted workouts touching goal speed. Use this number to define those sessions and to gut-check whether the goal itself squares with your recent results.
The pace and checkpoint figures are exact arithmetic on the distance and goal you enter — whether that goal suits your current fitness is a separate question the math cannot settle. General planning information for training and racing, not coaching and not medical advice.