Distance Converter
Convert distance between mm, cm, m, km, inch, foot, yard, mile units.
Input Information
Result
Distance Converter provides accurate conversions between various length units including metric and imperial systems. You can quickly change between millimeters (mm), centimeters (cm), meters (m), kilometers (km), inches, feet, yards, and miles.
Distance unit conversion is needed in travel, architecture, civil engineering, science experiments, and more. It is particularly useful in international environments that use both metric and imperial systems, when reading imported equipment spec sheets, or when working with overseas maps and drawings.
For students, it serves as learning material to understand unit concepts. For designers and builders, it is a practical tool for coordinating drawings and site measurements. It is also convenient in daily life for comparing heights, built-in wardrobe sizes, and exercise distances.
Conversion coefficients follow international standards (ISO). Inch and centimeter are strictly 1 inch = 2.54 cm, and mile is 1 mile = 1.609344 km. In aviation, nautical miles (1.852 km) are used, so choose the appropriate unit for your purpose.
Term Glossary
- Nautical Mile
- A length unit used in aviation and maritime, where 1 nautical mile = 1.852 km. It corresponds to 1 minute of latitude at the equator, and differs from the land mile.
- Metric vs Imperial
- The metric system uses mm·cm·m·km as the international standard, while the imperial system uses inch·foot·yard·mile. Conversion is needed as they are used interchangeably in some countries like the US.
- Choose the input unit to convert from. (m, km, mile, yard, ft, etc.)
- Enter the value you want to convert.
- Choose the output unit to convert to.
- Run the conversion and results in all units are shown automatically.
1 mile → km
1 mile is approximately 1.609 km. It is often used for marathons and road distance signs.
5 km → m / yd
5 km is 5,000 m and approximately 5,468 yards. It is a common running race distance.
1 inch → cm
1 inch is exactly 2.54 cm. It is used for screen sizes and small object lengths.
Distance Unit Conversion Relationships
Calculation Example
Converting 100 yards to meters:
100 yard × 0.9144 = 91.44 m
Everyday Distance Comparisons
- Basketball court: 28 m, Football field length: 100~110 m
- Seoul to Busan: approx. 325 km, Earth circumference: approx. 40,075 km
Metric vs Imperial
- Most countries except the US, Liberia, and Myanmar use the metric system.
- UK road signs display both meters and miles.
Aviation Distance
- Aviation uses nautical miles (1.852 km), where 1 nautical mile equals 1 minute at the equator.
- Map distance and actual flight distance may differ.
Architecture and Civil Engineering
- Convert drawing units (feet/inches) to site units (m) to reduce errors.
- Consider margins when calculating material lengths.
Exercise Record Keeping
- Record running distances in both km and mile for comparison.
- Unify distance units when converting pace.
Decimal Caution
- Record significant figures matching precision in precise measurements.
- Specify units to prevent accidents caused by unit confusion.
QWhat is the difference between the metric and imperial systems?
The metric system (SI) uses meters (m) and kilometers (km) and is used in most countries. The imperial system uses miles, yards, feet, and inches, mainly in the US and UK.
QWhat is the conversion factor from miles to kilometers?
1 mile is exactly 1.609344 km. As a quick estimate, 1 mile ≈ 1.6 km.
QWhen should I use each unit?
In metric countries, use meters (m) and centimeters (cm) for short distances and kilometers (km) for long ones. In the US, miles are used for roads, and feet and inches for height and short lengths.
QWhat is a nautical mile?
A nautical mile is used in aviation and maritime navigation, equal to about 1.852 km. It corresponds to one minute of latitude and is used in navigation and GPS.
QHow are precision and rounding handled?
Conversion results are shown to up to 6 decimal places. Large numbers use thousands separators, and very small values are shown in exponential notation.