Race distances
5K = 3.11 miles. 10K = 6.21 miles. Half marathon = 21.0975 km = 13.1 miles. Marathon = 42.195 km = 26.2 miles. One kilometer is 0.621 miles and one mile is 1.609 km. Our km to miles converter handles any distance.
Fall race season
Autumn is the peak season for big-city marathons and local turkey trots around Thanksgiving, which are usually 5K or 10K. If you're training for one, knowing your pace in both units helps because many race courses mark both kilometers and miles.
Calculating pace
Pace = time ÷ distance. Running a 5K in 30 minutes is a pace of 6:00 per kilometer, or about 9:39 per mile. To convert pace per km to pace per mile, multiply by 1.609; to go from per mile to per km, divide by 1.609.
Estimating finish times
Finish time = pace × distance. At 5:30 per km, a 10K takes 55 minutes and a half marathon about 1:56. For longer races most runners slow down, so add a few seconds per km to your shorter-race pace when predicting a marathon. Use our hours to minutes converter for time arithmetic.
Training basics
A common beginner rule is to increase weekly distance by no more than about 10% at a time. Most runs should be at an easy, conversational pace, with one faster workout and one long run per week. Rest days help your body adapt.
Fueling and hydration
For runs over about 60 to 90 minutes, many runners take carbohydrates, often 30 to 60 g per hour, and drink to thirst. Practice your race-day nutrition during training. Our water intake guide covers daily hydration.
Calories burned
A rough estimate is that running burns about 1 calorie per kilogram of body weight per kilometer. A 70 kg runner burns around 350 calories in a 5K and nearly 3,000 in a marathon.
Walking instead
A brisk walking pace is about 10 to 12 minutes per km, so a 5K walk takes 50 to 60 minutes, a great goal for beginners.
Frequently asked questions
How many miles is a 5K?
3.11 miles.
How many miles is a half marathon?
13.1 miles (21.0975 km).
How do I convert pace per km to pace per mile?
Multiply the pace per km by 1.609.
How long does a 10K take at 6:00 per km?
One hour.