How Many KM in a Half Marathon? Distance & Pace Chart

ByNathan Updated onNovember 1, 2026

A half marathon is exactly 21.0975 kilometers (km), or approximately 21.1 km and 13.1 miles. That is 21,097.5 meters from start to finish. If you are checking the distance, converting miles to kilometers, or planning your half-marathon pace, the quick charts below provide the answer first. Be sure to check out the RunDreamAchieve YouTube channel for weekly running tips and our running shoe reviews page for more details.

Half Marathon Distance: Kilometers, Miles and Meters

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• A training plan built specifically for your goal
• Personalized training paces
• Long runs, tempo runs, threshold workouts, interval sessions, recovery runs, and easy runs
• Peak weekly mileage matched to your experience level
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• Ongoing plan adjustments as your fitness improves

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How Far is a 1/2 Marathon in Kilometers?

The exact distance is 21.0975 kilometers, or 21.1 km when rounded to one decimal place. To race faster, practice sustainable pacing in selected workouts while keeping enough easy running to recover.

There is no universal percentage of mileage that every runner should complete at half-marathon pace. For many recreational runners, one threshold or race-specific workout per week alongside easy running and a long run is a more sustainable starting point.

So, in order to get the best results start studying what the best do. Also, how they think. Remember, mental training is a massive part of success. That being said, most runners only focus on physical training and neglect this vital clue. I would always visualize myself running under 2:22:00 for the marathon when my PR was 2:43:36 for the marathon.

I know it was a major reason I ended up lowering my personal best down to 2:19:35. Of course, I was still training far below my goal marathon race pace. What I did know is the world’s best spent time mentally rehearsing success before it became a reality.

What is the Average Time for a Half Marathon?

Half-marathon finish times vary considerably by age, experience, course, and the group of runners measured. Rather than treating a single average as a benchmark for everyone, use your recent race results and training to set a realistic target. A two-hour half marathon, for example, requires roughly 5:41/km.

One of the best ways to run faster over this distance is to start running faster during your long runs. Do you usually run long and slow on your weekend long runs? If so, I recommend doing a varied paced long run one weekend followed the next weekend by an easy, relaxed long run.

Again, the focus here is to run faster over the half marathon distance. Athletes seeking answers to how many km in a half marathon are also seeking how to cover the distance in timely fashion as well. So, you want to spend longer periods of time running at a higher percentage of your maximum heart rate. Below are some examples of what a varied pace long run may look like…

• 2 mile warm-up, 4 miles@10 seconds slower than goal half marathon race pace, 2 miles easy, 1 mile all out, 2 miles easy, 3 miles@5 seconds below goal half marathon pace
• 1 mile warm-up, 14 miles@160 beats per minute (85% of maximum heart rate), 2 mile cool-down
• 2 mile warm-up, 4 miles@165 beats per minute, 4 miles@140BPM, 4 miles@175BPM, 4 miles easy cool-down

How Many KM Should You Run a Week for Half Marathon?

I am a big believer in quality versus quantity. Of course, we all come from different backgrounds. You may be seeking to run your first half marathon or an elite athlete. So, the amount of mileage run is going to vary from athlete to athlete.

Around 20–40 km per week may be a workable range for some first-time half-marathon runners, but others need a lower starting point or more time to build safely. Consistency and gradual progression matter more than reaching a fixed number. Again, it isn’t as much the volume as it is the quality of the work output you are putting in that matters most.

How often are you training at or below your goal race pace is what will set you up for success. So, if the percentage is far too low. How well do you think you’ll be able to sustain your goal pace in the race? How many km in a half marathon? 21.1 and to run them faster then your competition you have to think and train like a world-class runner.

Easy mileage builds the aerobic foundation needed to sustain a half-marathon effort. Add harder workouts strategically, rather than turning every run into a race. The goal is to arrive at the start line healthy and prepared to hold a realistic pace.

If you struggle to hold your goal pace, review your starting pace, aerobic base, fueling, conditions, and recovery before assuming you need more intense sessions. Some experienced runners benefit from faster intervals, but VO2 max workouts are not mandatory every week for every half-marathon runner.

What Happens to Your Body after a Half Marathon?

For runners with an established base, faster workouts can complement half-marathon training. The following are demanding examples, not a beginner checklist; reduce the number of repetitions or choose easier sessions when appropriate:

• 1 mile warm-up, 16x400m@3K to 5K race pace, 1 mile cool-down
• 2 mile warm-up, 3x2mile on the track@10K race pace, 1 mile cool-down
• 20 minutes of fartlek running 1 minute hard/1minute easy

After a half marathon, temporary muscle soreness and fatigue are common. Prioritize sleep, food, fluids, and a few days of easier activity or rest based on how you feel. Return to hard training gradually; ice or Epsom salt baths are optional comfort measures, not essential recovery treatments.

Hydration and carbohydrate needs depend on pace, weather, sweat rate, and race duration. Practice your race-day drinking and fueling plan during long runs. Avoid both dehydration and excessive fluid intake; drink according to a sensible individualized plan.

You can plan water stops or carry a bottle during long runs, then rehearse the same approach on race day. For longer efforts, many runners benefit from carbohydrates during the race, but the amount should be tailored and practiced in advance. The half marathon is long enough that pacing and fueling deserve attention.

Half Marathon Distance: Frequently Asked Questions

Is a half marathon 21 km or 21.1 km?

The official distance is 21.0975 km. Saying 21.1 km is the normal rounded form; 21 km is slightly short.

How many miles is 21.1 km?

21.1 km is approximately 13.11 miles. A precisely measured half marathon is 21.0975 km, or about 13.1094 miles.

Is a half marathon exactly 13 miles?

No. A half marathon is approximately 13.1094 miles, so it is about 0.1094 miles longer than 13 miles.

How many meters are in a half marathon?

A half marathon is exactly 21,097.5 meters.

What pace is needed for a two-hour half marathon?

You need to average approximately 5:41 per kilometer or 9:09 per mile across the full 21.0975 km.

How far should my longest run be before a half marathon?

That depends on experience and training history. Many beginner plans build toward roughly 16–19 km (10–12 miles), while experienced runners may run farther. Progress gradually and prioritize recovery.

Closing Thoughts

A half marathon is 21.0975 km exactly, which is 13.1094 miles. Your finishing time depends on fitness, pacing, course conditions, and preparation. I also highly recommend subscribing to the RunDreamAchieve YouTube channel mentioned above. I created new videos each week to help successful athletes such as yourself get to the next level in their training and racing. How often do you spend time mentally rehearsing yourself succeeding in your race? Do you often times dream about crossing the finish line with your goal time on the clock? If not, then I want you to start spending 10 to 15 minutes each day doing this.

The perfect time is when you go to bed or when you are first waking up in the morning. The best middle to long distance runners know how vital mental training is. So, do what they do. Lastly, stay as relaxed as you can in training and when you race. Have you ever watched a world-class runner? They always are relaxed and in control. You will notice sometimes they even smile in their races.

I noticed this watching elite marathon runner Eliud Kipchoge. Success leaves clues. There is no sense in wasting mental or physical energy in your race. So, practice staying as calm and relaxed as you can in training and when you race. You can leave being tense, up tight and nervous for your competition to worry about.