25K Pace Calculator
8:03/mi
7.46mph
25.000 km · ~15.53 mi
- First half
- 8:03/mi
- Second half
- 8:03/mi
- 12.5K split
- 1:02:30
Checkpoints
5K
3.11 mi
10K
6.21 mi
12.5K (halfway)
7.77 mi
15K
9.32 mi
20K
12.43 mi
Half marathon
13.11 mi
Finish
15.53 mi
Kilometer splits
1 km
1.00 km
2 km
2.00 km
3 km
3.00 km
4 km
4.00 km
5 km
5.00 km
6 km
6.00 km
7 km
7.00 km
8 km
8.00 km
9 km
9.00 km
10 km
10.00 km
11 km
11.00 km
12 km
12.00 km
13 km
13.00 km
14 km
14.00 km
15 km
15.00 km
16 km
16.00 km
17 km
17.00 km
18 km
18.00 km
19 km
19.00 km
20 km
20.00 km
21 km
21.00 km
22 km
22.00 km
23 km
23.00 km
24 km
24.00 km
25 km
25.00 km
Mile splits
1 mi
1.00 mi
2 mi
2.00 mi
3 mi
3.00 mi
4 mi
4.00 mi
5 mi
5.00 mi
6 mi
6.00 mi
7 mi
7.00 mi
8 mi
8.00 mi
9 mi
9.00 mi
10 mi
10.00 mi
11 mi
11.00 mi
12 mi
12.00 mi
13 mi
13.00 mi
14 mi
14.00 mi
15 mi
15.00 mi
Finish
15.53 mi
Same pace, other distances
Half marathon
13.11 mi at this pace
30K
18.64 mi at this pace
Even pace for 25.000 km, not a race-equivalence predictor. The half marathon and 30K rows are this pace held for 21.0975 km and 30 km, not predictions. 20K pace · 15K pace · half marathon pace · marathon pace · race fueling · race time predictor · race pace band.
Worked examples
2:05:00 25K
8:03 /mi · 5:00 /km · 12.5K 1:02:30
1:40:00 25K
6:26 /mi · 4:00 /km · 12.5K 50:00
2:30:00 25K
9:39 /mi · 6:00 /km · 12.5K 1:15:00
Who runs a 25K
The 25K sits in the gap between the half marathon and the marathon: 15.53 miles, about 2.4 miles past 13.1. The River Bank Run in Grand Rapids, Michigan is one of the best-known 25K road races in the US, and plenty of trail races use the distance too. For marathoners, a spring or fall 25K is a common checkpoint: long enough to rehearse goal pace, shoes, and fueling, short enough to be back to normal training within days.
Pacing a 25K
Treat the first 10K as a warm-up at goal pace, not a time trial. The 12.5K mark is halfway: at 2:05:00 even that is 1:02:30, and on a 3% negative split it is 1:04:23 with the back half at 4:51/km. The half marathon timing mat, if your course has one, comes at 1:45:29 on that schedule, with about 3.9 km left. The race is really decided between 20K and the finish, so save something for it.
Fueling for a two-hour effort
At around two hours, most runners finish a 25K past the point where carbohydrate on the course starts to matter. A common approach is a gel or sports drink every 30–45 minutes, starting early rather than waiting until you feel flat, with water at aid stations. Rehearse the exact product in long runs. The race fueling calculator turns a finish time into carbs per hour and gels to carry.
How it works
Arithmetic, not physiology. Distance is locked at 25.000 km (15.53428 mi). Pace = time / distance. This is even 25K race pace, not race-equivalence. For a half→25K or 25K→marathon estimate, use the race time predictor (Riegel). This page does not clone VDOT or McMillan tables.
- pace = time / 25.000 km
- 25K = 25.000 km = 15.534279806 mi
- halfway = 12.5 km = pace × 12.5 km
- half / 30K at this pace = pace × 21.0975 km / 30 km
- 1 mile = 1.609344 km
Same even-pace math as the 20K pace calculator · 15K pace · 10 mile pace · half marathon pace · marathon pace · split calculator · pace calculator · race pace band.
Pacing aid only. Not a training plan. Not medical advice.
FAQ
What pace for a 2:05 25K?
A 2:05:00 25K is 8:03 per mile, or 5:00 per kilometer, at even pace. That is the same even-pace band as a 1:40:00 20K or a 50:00 10K, held for 25 km. Distance is locked at 25.000 km (15.53 mi). There is no Calculate button; pace updates live.
How many miles is a 25K?
A 25K is 25.000 kilometers, which is 15.53 miles (15.534279806 mi using 1 mile = 1.609344 km). It is 3.9025 km (about 2.4 mi) longer than a half marathon and 17.195 km shorter than a marathon.
What is the halfway split for a 25K?
Halfway is the 12.5K mark (about 7.77 mi). At 2:05:00 even pace you pass 12.5K in 1:02:30. On a slight 3% negative split you pass it in 1:04:23 (5:09/km), then close at 4:51/km and still finish in 2:05:00.
Where do I pass the half marathon in a 25K?
The 21.0975 km half-marathon point comes about 3.9 km before the finish. At 2:05:00 even pace (5:00/km) you pass it in 1:45:29. The Checkpoints list shows it alongside 5K, 10K, 15K, and 20K, so you can see whether you are on schedule with roughly 20 minutes to run.
Do I need to fuel during a 25K?
Most runners finish a 25K somewhere between about 1:45 and 3:00, which is long enough that many take carbohydrate on the course, often a gel or sports drink every 30–45 minutes from early in the race. Practice it in training. The fueling calculator turns your finish time into carbs per hour and gels to carry; this page only does pace math.
Is a 25K good marathon training?
Many marathoners race a 25K 6–10 weeks before a marathon as a long run at or near goal marathon pace: it is long enough to test shoes, fueling, and pacing, but short enough to recover from quickly. This page only shows the pace math, not a training plan.
Should I run a 25K at even pace or negative split?
Even pace or a slight negative split is the usual advice for road races this long. Starting a few seconds per km too quick tends to cost more over the last 5 km than it saved early. Toggle Even / Negative to compare both clocks for the same finish time.
Does this predict my 25K from a half marathon?
No. This page is even-pace arithmetic for 25.000 km. The half-marathon and 30K rows show the same pace held over those distances, not a prediction, and nothing here is VDOT or McMillan. For a fatigue-based estimate from a recent race, use the race time predictor (Riegel).