Convert Distance
Conversion Formula
About Kilometers and Miles
Kilometers are the standard unit of distance in most countries worldwide, part of the metric system. Miles are primarily used in the United States, United Kingdom, and a few other countries.
When You'll Need This
- Running & fitness: Race distances are often listed in both units (5K, 10K, marathon)
- Travel: Speed limits, road signs, and maps use different units depending on country
- Vehicle displays: Switching between metric and imperial odometer readings
- Navigation apps: Setting your preferred distance unit
Quick Mental Math Trick
To roughly convert km to miles: multiply by 0.6 (or use 5/8). For example, 10 km × 0.6 = 6 miles (actual: 6.21 mi). To go from miles to km: multiply by 1.6. For example, 5 miles × 1.6 = 8 km (actual: 8.05 km).
History
The kilometer was introduced with the metric system in France in 1799, defined as 1/10,000 of the distance from the equator to the North Pole. The mile originated from the Roman "mille passus" (thousand paces), standardized in England in 1592 as exactly 5,280 feet.
Frequently Asked Questions
How many miles is 1 kilometer?
1 kilometer equals 0.621371 miles. A quick mental shortcut is to multiply kilometers by 0.6 or use the fraction 5/8 for a close approximation.
How many kilometers is 1 mile?
1 mile equals exactly 1.609344 kilometers. To roughly convert miles to km, multiply by 1.6.
How far is a 5K in miles?
A 5K race is 5 kilometers, which equals 3.107 miles.
How far is a marathon in miles and kilometers?
A marathon is 42.195 kilometers or 26.219 miles. A half marathon is 21.0975 km or 13.109 miles.
Which countries use kilometers and which use miles?
Most countries worldwide use kilometers as the standard distance unit. The United States, the United Kingdom (for road signs), Myanmar, and Liberia still use miles for road distances.
How do I quickly convert km to miles in my head?
Multiply the kilometer value by 0.6 for a quick estimate. For example, 10 km x 0.6 = 6 miles (actual is 6.21). For better accuracy, use the fraction 5/8.
Are nautical miles the same as regular miles?
No. A nautical mile is 1.852 kilometers (1.151 regular miles). Nautical miles are used in aviation and maritime navigation. This converter handles statute (regular) miles only.
Why is a mile 5,280 feet?
The mile originated from the Roman mille passus (thousand paces, about 5,000 feet). In 1592, England redefined it as 5,280 feet (8 furlongs) to align with the furlong used in land surveying.
Related Tools
- Miles to Kilometers Converter -- convert miles to kilometers with the same visual scale.
- Speed Unit Converter -- convert between km/h, mph, m/s, and knots.
- Pace Calculator -- calculate running pace in min/km or min/mile.
- Weight Unit Converter -- convert between metric and imperial weight units.
- Temperature Unit Converter -- convert between Celsius, Fahrenheit, and Kelvin.
Privacy & Limitations
- All calculations run entirely in your browser -- nothing is sent to any server.
- Results are estimates and may vary based on actual conditions.
Related Tools
View all toolsPercentage Calculator
Calculate percentages, find X% of Y, percentage change
BMI Calculator
Calculate Body Mass Index from height and weight
Weight & Mass Converter
Convert between metric and imperial weight units
Length Converter
Convert between metric and imperial length units
Loan Calculator
Calculate monthly payments and total interest
Word Counter
Count words, characters, and sentences
This tool FAQ
How many miles is 1 kilometer?
1 kilometer equals 0.621371 miles. A quick mental shortcut is to multiply kilometers by 0.6 or use the fraction 5/8 for a close approximation.
How many kilometers is 1 mile?
1 mile equals exactly 1.609344 kilometers. To roughly convert miles to km, multiply by 1.6.
How far is a 5K in miles?
A 5K race is 5 kilometers, which equals 3.107 miles.
How far is a marathon in miles and kilometers?
A marathon is 42.195 kilometers or 26.219 miles. A half marathon is 21.0975 km or 13.109 miles.
Which countries use kilometers and which use miles?
Most countries worldwide use kilometers as the standard distance unit. The United States, the United Kingdom (for road signs), Myanmar, and Liberia still use miles for road distances.
How do I quickly convert km to miles in my head?
Multiply the kilometer value by 0.6 for a quick estimate. For example, 10 km x 0.6 = 6 miles (actual is 6.21). For better accuracy, use the fraction 5/8.
Are nautical miles the same as regular miles?
No. A nautical mile is 1.852 kilometers (1.151 regular miles). Nautical miles are used in aviation and maritime navigation. This converter handles statute (regular) miles only.
Why is a mile 5,280 feet?
The mile originated from the Roman mille passus (thousand paces, about 5,000 feet). In 1592, England redefined it as 5,280 feet (8 furlongs) to align with the furlong used in land surveying.