Easily convert km to miles, and vice versa

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The four most prestigious ultras in the world fit this format: the Western State 100-Mile Endurance Run, in California; the Hardrock 100, in Colorado; the Ultra-Trail du Mont-Blanc, in Chamonix; and La Diagonale des Fous, the flagship race of the Grand Raid de la Réunion. To fully appreciate the XXL format of these trails, it is useful to convert the distances given in miles into kilometers, and vice versa (km to miles). We'll help you easily make the conversion. We'll also show you how to switch from a pace expressed in min/mile to a pace in min/km.  

Indeed, metric/kilometric systems are not adopted worldwide. For example, the mile, or international land mile, is used as a unit of measurement in the United States, the United Kingdom, and various Commonwealth countries. In these countries, speed limit signs on the road or vehicle odometers are indicated in miles per hour. 🏁 

Although the mile event is not an Olympic distance, it is still practiced in North American universities. It corresponds to four laps of a 400-meter stadium... plus nine meters.  

The Briton Roger Bannister was the first man to break the mythical 4-minute mile barrier on May 6, 1954, with a time of 3 minutes 59 seconds and 4 tenths. Today, the world records for the mile belong to Moroccan, Hicham El Guerrouj, at 3 minutes 43 seconds and 13 hundredths (record set in 1999); and to Kenyan, Faith Kipyegon, at 4 minutes 7 seconds and 64 hundredths (achievement in 2023). The Norwegian rocket, Jakob Ingebrigtsen, nearly broke the world record with his 3 minutes 43 seconds and 73 hundredths. 🚀 

The mile is a unit of measurement that corresponds precisely to 1,609.344 meters. To convert from miles to kilometers, simply multiply the distance by 1.609.   

Thus, an ultra-trail of exactly 100 miles equals 100 x 1.60934 = 160,934 kilometers. This is a minimum. As you will see further, ultra-trails can exceed the 100 miles barrier by quite a bit.  

Conversely, to convert from a distance expressed in kilometers to a distance in miles, you must divide this distance by 1.60934 or, if preferred, multiply it by 0.62137. 

For example, the 2024 edition of the Ultra-Trail du Mont-Blanc course was 176.4 kilometers, i.e., 176.4 x 0.62137 = 109.6 miles.  

In road racing, a marathon equals precisely 42.195 x 0.62137 = 26.218 miles,rounded to 26.2 miles. A half-marathon equals 13.1 miles. 🧮 

To save you from calculations, find the conversions of a distance in mile to a distance in kilometer in the table below. 

Because the kilometer and the mile are two different measurement units, a pace expressed in min/mile and a pace expressed in min/km are not necessarily identical. You may also have friends from Anglo-Saxon countries on Strava who set their pace in minutes and seconds per mile. At first glance, it's not easy to envision these paces if you're used to min/km. For example, is a marathon pace of 6 minutes per mile fast? 

Conclusion: yes, this marathon pace is fast for most runners! 🤯 

In conclusion, accurately converting between kilometers and miles is a fundamental skill for anyone dealing with distance, especially in sports or travel. While the kilometer to mile conversion and vice versa might seem daunting, understanding that the kilometer is a core unit of length within the International System of Units (the metric system) and the mile belongs to imperial systems is key. Tools like a mile calculator make it simple to convert kilometers to miles or to convert kilometer values as needed. This ease of mile conversion allows us to seamlessly express distance, regardless of the measurement system being used.
You now have all the tools in hand to convert km to miles, as well as your kilometer paces to mile paces. So, when's your next (or first) race in the United States or the United Kingdom? 🫢