Running Split Calculator

Get split times per kilometre or mile for a goal finish time, with even or negative splits.

Race distance	10
Distance in	miles
Goal time (h:mm:ss)	0:50:00
Negative split	2 % faster second half

Race distance

Distance in

Goal time (h:mm:ss)

Negative split

% faster second half

Average pace

5:00 per mi

First half 5:03, second half 4:57 per mi, finishing in 50:00.

Split times

Split	Pace	Elapsed
1 mi	5:03	5:03
2 mi	5:03	10:06
3 mi	5:03	15:09
4 mi	5:03	20:12
5 mi	5:03	25:15
6 mi	4:57	30:12
7 mi	4:57	35:09
8 mi	4:57	40:06
9 mi	4:57	45:03
10 mi	4:57	50:00

About the Running Split Calculator

Enter the race distance, your goal time and how much faster you want to run the second half. The calculator gives the pace for each half and a table of every split with the elapsed time, so you can check your watch against the plan during the race.

Even pacing is the most efficient way to race for most runners. A negative split, running the second half slightly faster, helps avoid starting too fast; elite marathoners often run the second half 1–2% faster. Enter 0 for even splits.

The formula

Average pace = goal time ÷ distance; second-half pace = first-half pace × (1 − negative %)

Worked example

10 km in 50:00 with a 2% negative split

Average pace: 5:00 per km
First 5 km at 5:03 per km, reaching 25:15
Last 5 km at 4:57 per km, finishing at 50:00

Things to keep in mind

Splits are rounded to the nearest second; the elapsed column keeps the exact total.
Doesn't adjust for hills; on a hilly course run by effort and use the splits as a guide.

Questions people ask

How much faster should the second half be?

1–3% is typical; more is risky unless you're very experienced.

Should I bank time early?

Usually not: going out too fast costs more time later.

Can I plan a positive split?

Yes, enter a negative number, for example −2 for a second half 2% slower.