Conversion Calculators(16)
Length, temperature, weight unit conversions
Length Converter
Convert between cm, m, km, inch, ft, mile and more.
Temperature Converter
Convert between Celsius, Fahrenheit, and Kelvin.
Weight Converter
Convert between kg, g, lb, oz and more.
Data Size Converter
Convert between B, KB, MB, GB, TB and more.
Area Converter
Convert between ㎡, pyeong, acres, hectares and more.
Volume Converter
Convert between mL, L, gallons, cups and more.
Speed Converter
Convert between km/h, m/s, mph, knots and more.
Time Converter
Convert between seconds, minutes, hours, days and more.
Pressure Converter
Convert between Pa, atm, bar, psi and more.
Energy Converter
Convert energy units.
Angle Converter
Convert angle units.
Force Converter
Convert force units.
Power Converter
Convert power units.
Fuel Unit Converter
Convert fuel economy units.
Number System Converter
Convert number systems.
Cooking Unit Converter
Convert cooking units.
Overview
Our unit conversion calculator collection lets you quickly and accurately convert every unit you need in daily life and professional fields, including length, weight, temperature, area, volume, speed, pressure, time, and data size. Beyond basic conversions like centimeters to inches, kilograms to pounds, and Celsius to Fahrenheit, it also covers scientific and engineering units such as energy (J, cal, kWh), force (N, kgf, lbf), power (W, hp), and angle (degrees, radians). Use these tools for checking sizes while shopping internationally, converting measurement units in cooking recipes, comparing fuel economy across regions, and converting number systems in programming. All calculations are based on internationally standardized conversion factors with full decimal precision, and conversions between the metric system and the imperial system are handled seamlessly. Simply enter a value and get instant results without having to memorize any conversion formulas.
Tips
- ✔When converting between imperial units used in countries like the US and metric units used in Korea, watch out for rounding errors. For precision work, make sure to retain enough decimal places.
- ✔Temperature conversion between Celsius and Fahrenheit uses a formula, not a simple ratio: F equals C times 9/5 plus 32. Common conversions include cooking temperatures (180C equals 356F) and body temperature (36.5C equals 97.7F).
- ✔The Korean 'pyeong' unit has officially been replaced by square meters, but it is still commonly used in real estate transactions. Convert using 1 pyeong equals approximately 3.3058 square meters.
- ✔When converting data sizes, understand the difference between 1 KB equals 1,000 bytes (SI standard) and 1 KiB equals 1,024 bytes (binary standard). Hard drives use SI units while operating systems use binary units, which is why displayed capacity often differs from the advertised size.
- ✔When following international recipes, converting volume units like cups, tablespoons, and teaspoons to milliliters ensures accurate measurements. One US cup is about 237 mL, and one tablespoon is about 15 mL.
- ✔When comparing fuel economy internationally, you need to convert between km/L (Korea), MPG (US/UK), and L/100km (Europe). Note that higher values mean better efficiency for km/L and MPG, while lower values are better for L/100km.
- ✔In speed units, 1 knot equals 1.852 km/h. Knots are used in aviation and maritime contexts, so converting is necessary to understand weather reports and navigation speeds in everyday terms.
- ✔Pressure units vary by field. Meteorology uses hPa (mbar), tire pressure uses psi, and science commonly uses Pa or atm. For reference, 1 atm equals 101,325 Pa equals 14.696 psi.
FAQ
Q. What is the difference between the metric system and the imperial system?
The metric system uses meter (m), kilogram (kg), liter (L), and other base-10 units as the international standard, adopted by most countries including Korea. The imperial system uses inches, pounds, gallons, and similar units, and is officially used primarily in the United States, Myanmar, and Liberia. The metric system offers simple conversions through powers of ten, while the imperial system has irregular conversion ratios such as 12 inches to 1 foot and 3 feet to 1 yard.
Q. When are Celsius, Fahrenheit, and Kelvin used respectively?
Celsius is used for everyday purposes in most countries including Korea, with water freezing at 0 degrees C and boiling at 100 degrees C. Fahrenheit is mainly used in the United States, with water freezing at 32 degrees F and boiling at 212 degrees F. Kelvin is the absolute temperature unit used in scientific research, where 0 K (absolute zero) equals minus 273.15 degrees C. Since Kelvin and Celsius share the same scale interval, the conversion is simply K equals degrees C plus 273.15.
Q. How many square meters is exactly one pyeong?
One pyeong is approximately 3.3058 square meters, equivalent to the area of a square with sides of about 1.818 meters. Since 2007, Korea has mandated the use of square meters as the official unit, but pyeong is still commonly used in the real estate market by convention. To convert square meters to pyeong, multiply by 0.3025. For example, 84 square meters is about 25.4 pyeong.
Q. What is the difference between MB and MiB in data capacity?
MB (megabyte) follows the SI international standard where 1 MB equals 1,000 KB or 1,000,000 bytes, and is the basis used by hard drive manufacturers and telecommunications companies. MiB (mebibyte) follows the binary standard where 1 MiB equals 1,024 KiB or 1,048,576 bytes, and is used internally by operating systems. This difference is why a 1 TB hard drive shows up as approximately 931 GiB in your operating system, making it appear to have less capacity than advertised.
Q. How do I convert sizes when shopping from international retailers?
For shoes, Korea uses millimeters, the US uses US sizes, and Europe uses EU sizes. For example, Korean 260 mm corresponds to US mens 8, US womens 9.5, and EU 42. For clothing, Korean 100 (L) roughly corresponds to US M to L and EU 50. However, since sizing varies by brand, the most accurate approach is to check the actual measurements in centimeters or inches and use a length converter to compare.
Q. What are the most common unit conversions used in cooking?
In Korean cooking, the basic units are keun-sul or tablespoon (15 mL), jageun-sul or teaspoon (5 mL), and paper cup (180 mL). Western recipes use cup (about 237 mL), tablespoon (about 15 mL), and teaspoon (about 5 mL). For weight, 1 oz is about 28.35 g and 1 lb is about 453.6 g. Oven temperatures are often given in Fahrenheit, so knowing that 350 F equals 177 C and 400 F equals 204 C is very helpful.
Q. Where is number system conversion used?
Binary (base 2) is the fundamental system used by computers to process all data internally. Octal (base 8) is used for Linux file permissions, such as chmod 755. Hexadecimal (base 16) is widely used for web color codes like #FF5733, memory addresses, and MAC addresses. Number system conversion is an essential skill for anyone working in programming or networking.
Related Categories
Unit conversions for energy, force, and pressure are essential in physics and chemistry experiments, and using them alongside science calculators ensures accurate processing of experimental data.
Mathematical concepts such as number system conversion and ratio calculations form the foundation of unit conversion, and combining them with percentage or ratio calculators makes them even more effective.
Unit conversions are frequently needed in daily life for international travel, online shopping, and cooking, and they can be used alongside date and time calculators.