How Long Is a Half-Marathon?

Man stretching next to a woman before a half marathon

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A half-marathon is 13.1 miles or 21 kilometers. This is exactly half the distance of a full marathon (26.2 miles). It's a good goal for runners who have already completed a 5K (3.1 mile) race or a 10K (6.2 mile) race and are looking for a new challenge. If you can complete 3 miles, you can start to train for a half-marathon.

When running your first half-marathon, you may complete it in 2 to 3 hours. If you use the run/walk method or you are a brisk walker, you may take a bit longer. The cut-off time for finishing a half-marathon is usually set at 3.5 to 4 hours, depending on the race.

How Many Miles is a Half Marathon?

A half-marathon is equal to 13.1 miles, which is 21 kilometers. The distance of a full marathon is twice as long, 26.2 miles.

Choosing a Half-Marathon as Your Running Goal

The half-marathon is a popular race distance among runners because many see it as a worthwhile challenge that's not as time-consuming or physically exhausting as training for a full marathon. Half-marathon races are also fairly easy to find, as more and more keep popping up across the country.

Some runners also see running a half-marathon as a good excuse to travel to a new city or train for a race with family or friends. Half marathons may benefit specific charities, so some runners participate as a way to support a good cause. If you are a slow runner or a walker, half-marathons often have more achievable cut-off times than marathons.

What to Consider Before a Half-Marathon

There are a few things to consider before committing to a half-marathon, including benefits and possible effects on the body, time constraints, and goals.

Benefits of Doing a Half Marathon

Committing to a half-marathon may help you stay motivated to train. Having a goal-based outcome of completing a race can help you stay on track as you work toward race day. Training routines provide a solid structure for your exercise routine, allowing you to focus on progress and results as you work toward your goal.

Training for a half-marathon will boost your health by strengthening your cardiovascular system. This benefits your heart health, reducing your risks of diseases, cardiac events, and strokes. Exercise—like running—can also boost your immune health, reduce blood pressure, and lower cholesterol levels.

Physical Effects Of a Half-Marathon

If you want to run a long-distance race but are unsure of whether you can commit to a full marathon, a half-marathon is an excellent choice. Regardless of whether you choose to ever make the jump to a full marathon or not, you can reap the benefits of a consistent cardiovascular training schedule.

Additionally, full marathons are more physically demanding and taxing on the body than half-marathons. You will be less likely to experience injuries while performing a half-marathon than a full version. This leaves you in a better place physically to continue training or taking part in other forms of exercise.

Time Constraints and Goals

Half-marathon training does not take up as much time as a full marathon does. Making the physical leap to a full marathon requires your goal to be solely focused on training, recovering, and fueling from your marathon training.

Half-marathons are less demanding of your time and focus. While they are still a lofty goal that requires dedication, if you have a busier lifestyle or wish to divide your time between different hobbies or sports, a half-marathon may suit you better.

Half Marathon Training Plans

Before you make plans to train for a half marathon, you want to be sure you have a discussion with a healthcare provider. They can provide insight into whether or not this goal aligns with any limitations or medical conditions you might have.

Another factor in choosing a half-marathon is that you will only need to train for 12 weeks at a minimum. You can find a variety of half-marathon training schedules geared to different experience levels. Choosing the run that is right for you is largely based on personal preference. Here are some options to consider.

Run/Walk Half-Marathon Schedule

Some people enjoy using a run/walk half-marathon training program, which is designed to help you use the run/walk method to reach the finish line of your half-marathon. This approach is particularly useful people new to running or who have concerns like knee pain or asthma to still compete in half-marathon without overextending themselves. Make sure a healthcare provider has signed off on your goals as well.

To start this plan, you should have been run/walking for at least 2 months and should have a base mileage of about 8 to 10 miles per week. You also may want to try a few shorter races to see if this approach is one that you would enjoy using in a longer race.

Half-Marathon Training Schedule for Beginners

This training schedule is for beginner runners who want to get to the finish line of a half-marathon. It assumes that you already run at least 8 miles per week for at least 2 months. It lasts for 12 weeks and can be adapted to fit your schedule.

You also should consider getting fitted for a pair of running shoes that are designed for long-distance running. Once you find a pair that you like, think about purchasing a second pair for race day if you can. Ideally, you should put about 50 training miles on these shoes for race day. This way, they are broken in, but still have good support and plenty of tread for the race.

Half-Marathon Training Schedule for Advanced Beginners

This schedule is geared toward runners who can run 4 miles, and can commit to running 4 to 5 days per week. If you have never run a half-marathon before, but you're looking for a schedule that's a little more challenging than the half-marathon beginner schedule, this approach might be right for you.

This schedule assumes that you have some experience running races like a 5K or a 10K and that you have the time to commit to training. You also will need to consider how to hydrate during your training and may want to experiment with energy gels or bars to keep your energy up. When running longer routes, you may need to plan for water stops or wear a hydration pack.

Half-Marathon Training Schedule for Intermediate Runners

If you've run at least one half-marathon and you're hoping to improve your time, you'll definitely need to add speed training to your regimen, if you haven't already. This training plan will help you run your fastest half-marathon.

To start this plan, you should already be running about 30 to 60 minutes a day, 5 days a week. In addition to logging enough miles, your training will likely also consist of cross training, interval work, pacing work, and tempo runs. All of these components are designed to help you improve your race time and set a personal record.

Half-Marathon Training Schedule for Advanced Runners

Training schedules geared toward runners with long-distance running experience are more individualized depending on where you need work. Before you start this training schedule, you need to be able to run 8 miles comfortably and be able to run 5 days a week.

Like the intermediate training program, your training will likely also consist of cross training, interval work, pacing work, and tempo runs. These different training elements can be customized to help you meet your race needs and goals.

A Word From Verywell

If you are brand new to running, you can look ahead to a half-marathon as a good challenge. But don't skimp on the basics. Steadily build up your running time and distance by no more than 10% per week. You also should focus on your running form.

Once you can run 3 miles at least 3 days per week, you can begin thinking about training for different race distances. Start with 5K races, so you become familiar with running in a race. Then you can start planning your training for a half-marathon. Also, be sure to discuss your running goals with a healthcare provider to determine what is right for you.

4 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Christine Luff, ACE-CPT
Christine Many Luff is a personal trainer, fitness nutrition specialist, and Road Runners Club of America Certified Coach.