Half marathon pace chart: finish times and pace per km

Half marathon pace: how it is calculated

A half marathon is 21.0975 km (13.1 miles). The average pace per kilometre is your finish time divided by the distance: to finish in 2 hours (120 minutes) you need about 5:41 per km, for 1:45 about 4:59, for 1:30 about 4:16. Speed in km/h is 60 divided by the pace expressed in minutes.

This guide gives you the chart ready to use, shows how to choose a realistic target from a recent race or workout, how to split the race into stages and why your watch will almost certainly read more than the official 21.0975 km. If you prefer to do the maths yourself, use our running pace calculator.

Chart: finish time and pace per km

Here are the average paces for the most common targets (pace per km, average speed): 1:20 = 3:48 per km, 15.8 km/h. 1:25 = 4:02, 14.9 km/h. 1:30 = 4:16, 14.1 km/h. 1:35 = 4:30, 13.3 km/h. 1:40 = 4:44, 12.7 km/h. 1:45 = 4:59, 12.1 km/h. 1:50 = 5:13, 11.5 km/h. 1:55 = 5:27, 11.0 km/h. 2:00 = 5:41, 10.5 km/h. 2:10 = 6:10, 9.7 km/h. 2:15 = 6:24, 9.4 km/h.

Paces are rounded to the second. For any time not in the chart, the rule is simple: every 10 seconds less per km saves about 3 minutes 31 seconds over the full distance.

For reference on other distances, at 5:00 per km you run 5 km in 25:00, 10 km in 50:00 and the marathon in about 3:31. At 6:00 per km: 5 km in 30:00, 10 km in 1:00:00 and the half in 2:06:35. For pace per mile, multiply the pace per km by 1.609.

Choosing the right target: three honest ways

First: start from a recent race. A 10 km run in normal conditions is the best indicator. Riegel's formula estimates the time over the longer distance by multiplying the time by the ratio of distances raised to the power of 1.06. Examples: a 40:00 10 km leads to about 1:28:15 in the half, 45:00 to about 1:39:17, 50:00 to about 1:50:19, 55:00 to about 2:01:21, 60:00 to about 2:12:23.

This estimate works if you have trained enough for the distance: someone who has run a half only once, or has done few long runs, often performs worse than the formula says. If you prepared with low volume, add a few minutes to be safe. Our marathon time calculator does this in one click for the half as well.

Second: start from a test. After at least three or four weeks of preparation, run a long workout with 8-10 km at the hypothetical race pace. If you finish feeling in control, the target is right. If you are at your limit, lower your ambitions. Third: start from feel. Half marathon pace is what you can sustain for about an hour and a half or two, with clearly demanding but still regular breathing. If you could still chat, you are too slow; if you cannot say two words, you are too fast.

Splits every 5 km and intermediate times

To aim for 1:45 (about 4:59 per km) the splits are: 5 km in 24:53, 10 km in 49:46, 15 km in 1:14:39, 20 km in 1:39:32 and finish in 1:45:00. To aim for 2:00 (about 5:41 per km): 5 km in 28:26, 10 km in 56:53, 15 km in 1:25:19, 20 km in 1:53:45 and finish in 2:00:00.

Write the splits on a wristband, on your GPS display or on a laminated card: in a race, with the breathing, the noise and the effort, doing mental maths is hard. Many watches let you load a race plan with the pace for each stage. Before the start also check where the kilometre markers are: the time at the marker counts more than the GPS time.

Remember that the first kilometre is almost always slower because of the crowd: do not try to make up the lost seconds with a sprint, spread them over the following kilometres.

Start, middle and finish: how to spread the effort

The most common mistake is starting too fast. Adrenaline makes you feel light and quick, but every second gained in the first quarter is paid back with interest after km 15. Aim for a first 5 km slightly slower than your average target (3-5 seconds per km), then settle on race pace between km 5 and 15, and keep something for the last 5 km.

A negative split, that is a second half a little faster than the first, is the safest strategy for inexperienced runners. No need to overdo it: 1-2 minutes of overall difference is enough. After km 15 the body starts to present the bill: if you feel good, it is time to speed up calmly; if you are at the limit, hold your pace and focus on posture and cadence.

Read also our guide to the first half marathon pacing strategy to learn how to handle aid stations, wind and the last kilometres.

Why your watch shows more than 21.0975 km

The official course is measured along the shortest possible line, the one a runner follows only if they hug every inside curve. In reality you drift wide, overtake and go round aid stations: it is normal for a GPS to record 21.2-21.4 km. As a result the average pace on your watch always looks faster than the real one, and at the end you will have run faster than the display says.

That is why it is better to look at the pace at the kilometre marker or, if your watch allows it, the pace of a manual lap pressed at the markers. Do not panic if at the finish the GPS reads 21.3 km: the official distance remains 21.0975. In tunnels or streets between tall buildings the signal may be less accurate: one more reason to trust the markers.

A watch is not everything: if you want to know more about the heart rate zones to use in training, you will find the details in heart rate zones: how to calculate and use them.

Hills, wind, heat: how much times change

The chart is for a flat course in normal weather. Elevation costs time: you slow on climbs and only partly recover on descents. If the course has 150-250 metres of climbing, think in effort rather than fixed pace: on climbs hold the same effort and accept slowing down, on descents do not launch yourself too much or you will pay with your legs.

Heat and humidity hurt performance much more than people think: above 20 degrees Celsius many runners see their pace drop noticeably, and it is wise to revise the target accordingly. A headwind slows you, a tailwind helps less than the headwind costs. If you can choose, pick races in spring and autumn, with cool temperatures and flat courses.

If you are looking for a race to sign up for, discover the 2027 race calendar with half marathons across Italy.

How to train to hold your target pace

Race pace is learned in training. After the base phase, add once a week a workout at half marathon pace: start with 3 repetitions of 2 km at race pace with 2 minutes of recovery, then move to 2 of 4 km, up to 8-10 km continuous. Once every 10 days run a long run up to 16-18 km at easy pace, and keep the rest of the week easy.

If you start from a good 10 km level, our 8-week half marathon plan guides you step by step. In the last week reduce volume following the principles of tapering and arrive at the start rested. To organise your long run with other runners, find group runs near you. See you on the road.