Units
Length, mass, temperature, and other unit conversions with fixed factors.
67 tools
Subcategories
- Unit Converter Pick a dimension, then convert. Temperature uses offset formulas. Fuel economy uses the mpg and L/100 km relation.
- AWG to mm² Convert American Wire Gauge to conductor cross section in mm² using ASTM B258. Gauge 4/0 is n = -3. This is diameter geometry, not a code ampacity table.
- Centimeters to Inches Centimeters to inches. 1 in = 2.54 cm.
- Feet and Inches Calculator Convert feet plus inches to decimal feet, total inches, centimeters, and meters. Split total inches into feet and leftover inches. Add or subtract two lengths. No adult-height 9 ft cap. Construction helper, not a growth chart.
- Feet to Centimeters Convert international feet to centimeters. One foot is exactly 30.48 cm. Type a decimal foot such as 5.5, not 5 feet 6 inches as two fields.
- Feet to Inches Feet to inches. 1 ft = 12 in.
- Feet to Meters Feet to meters. 1 ft = 0.3048 m.
- Feet to Millimeters Convert international feet to millimeters. One foot is exactly 304.8 mm. Type a decimal foot. Feet plus leftover inches as two fields belong on the height converter.
- Feet to Yards Convert feet to yards. Three international feet make one yard exactly. This page does not use the US survey foot. Height in feet and inches is a different job.
- Height Converter Feet and leftover inches to centimeters, or centimeters to feet and inches. Same inch factor as the length converter.
- Inches to Centimeters One inch is 2.54 centimeters exactly. This page locks those two units on the shared length engine.
- Inches to Feet Convert inches to international feet. Twelve inches make one foot. Both units rest on the 1959 inch of 0.0254 m. The list still holds millimeters, meters, yards, miles, and nautical miles.
- Inches to Meters Convert inches to meters. One inch is exactly 0.0254 m. This is the SI definition of the international inch, the same inch as inches to centimeters.
- Inches to Millimeters Inches to millimeters.
- Kilometers to Miles Kilometers to statute miles.
- Length Converter Convert a length with SI factors. One inch is 0.0254 meters exactly. For height in feet and inches, use the height page.
- Meters to Feet Meters to feet.
- Miles to Kilometers Convert statute miles to kilometers. One international mile is exactly 1.609344 km. Nautical miles (1852 m) sit on the same list under a different label.
- Millimeters to Inches Millimeters to inches.
- Shoe Size Converter Convert adult shoe sizes among US men, US women, UK, EU, and Mondopoint millimeters. The model uses last length: EU Paris point of 2/3 cm, UK barleycorn, US men = UK + 1, US women = US men + 1.5. Brands differ. This is not a fitting.
- Grams to Kilograms Convert grams to kilograms. One kilogram is 1000 grams exactly. This is the SI prefix, not a density tool and not a force converter.
- Grams to Ounces Grams to avoirdupois ounces.
- Kilograms to Pounds The pound is 0.45359237 kg exactly. This page locks kg to lb on the shared mass engine.
- Kilograms to Stone Kilograms to stone. 1 st = 6.35029318 kg.
- Pounds to Kilograms Multiply pounds by 0.45359237. Same mass engine as kilograms to pounds.
- Weight and Mass Converter Avoirdupois pound is 0.45359237 kg. Metric prefixes from the gram. Not a planetary gravity tool.
- Ounces to Grams Convert avoirdupois ounces to grams. One ounce is 1/16 of the international pound, so 1 oz = 28.349523125 g. Troy ounces for precious metal are not on this list.
- Ounces to Pounds Convert avoirdupois ounces to pounds. Sixteen ounces make one pound. This is mass, not US fluid ounces of volume.
- Stone to Kilograms Convert stone to kilograms. One stone is exactly 14 avoirdupois pounds, which is 6.35029318 kg. This is mass, not kilogram-force.
- Stone to Pounds Convert stone to avoirdupois pounds. One stone is exactly 14 pounds. Decimal stone such as 11.5 st is 161 lb. This page does not split 11 st 6 lb into two boxes.
- Celsius to Fahrenheit Multiply by 9/5 and add 32. Locked spoke of the temperature converter.
- Celsius to Kelvin Convert Celsius to kelvin with the offset K = C + 273.15. Absolute zero is 0 K, which is -273.15 °C. The engine rejects temperatures below that.
- Fahrenheit to Celsius F = C × 9/5 + 32 reversed.
- Temperature Converter F = C × 9/5 + 32. K = C + 273.15. Values below 0 K are rejected.
- Gallons to Liters Convert US gallons to liters. One US gallon is exactly 3.785411784 liters. The UK gallon is listed as Gallons (UK). This is the reverse of liters to gallons.
- Liters to Gallons Convert liters to US gallons. One US gallon is exactly 3.785411784 liters. The UK gallon is listed as Gallons (UK). This is liquid volume, not a dry measure.
- Milliliters to Fluid Ounces Convert milliliters to US fluid ounces. One US fluid ounce is 29.5735295625 ml. This is liquid volume, not the 28.35 g avoirdupois ounce.
- Volume Converter Convert volume units with fixed factors. Nothing uploaded.
- Acres to Hectares Convert acres to hectares with the international foot. One acre is 4046.8564224 m². One hectare is 10000 m². So 1 ac = 0.40468564224 ha. This is not a cadastral survey.
- Area Converter Convert area units with fixed factors. Nothing uploaded.
- Square Feet to Square Meters Convert square feet to square meters with the international foot. One square foot is exactly 0.09290304 square meters. This is not a cadastral survey.
- KPH to MPH Convert kilometers per hour to miles per hour. Divide km/h by 1.609344, the exact international-mile factor. Defaults start at km/h, the reverse of the mph to kph spoke.
- MPH to KPH Convert miles per hour to kilometers per hour. One international mile is 1609.344 m, so 1 mph = 1.609344 km/h exactly. This is not a speed camera.
- Speed Converter Convert speed units with fixed factors. Nothing uploaded.
- Bits to Bytes Convert bits to bytes. Eight bits make one byte. Kilobytes on this list use 1000. Kibibytes use 1024. Hard-drive marketing often uses 1000. RAM often uses 1024.
- Data Storage Converter Convert data units with fixed factors. Nothing uploaded.
- MB to GB Convert megabytes to gigabytes using SI prefixes: 1000 MB = 1 GB. Switch to mebibytes and gibibytes when you need 1024. This is storage size, not download time.
- Energy Converter Turn a stored quantity of energy into another unit. The SI unit is the joule. This is not a power converter and it does not turn watt-hours into milliamp-hours.
- Joules to kWh Convert joules to kilowatt-hours. 3,600,000 J equals 1 kWh. Default input 3,600,000 J. For utility and physics comparisons.
- kWh to Joules Convert kilowatt-hours to joules. One kWh is exactly 3,600,000 J (3.6 MJ). Default input 1 kWh. Energy units only, not power.
- mAh to Wh Convert milliamp-hours to watt-hours using voltage: Wh = (mAh / 1000) × V. Default 5000 mAh at 3.7 V is 18.5 Wh. Voltage is required. Not on the energy hub without voltage.
- Watt-Hours to mAh Convert watt-hours to milliamp-hours using a voltage you type. Wh = (mAh / 1000) × V. Milliamp-hours are charge, not energy, until you multiply by volts. The energy hub does not list mAh.
- Horsepower to Kilowatts Mechanical horsepower to kilowatts.
- Kilowatts to Horsepower Convert kilowatts to mechanical horsepower. One mechanical horsepower is 745.6998715822702 W, so 1 kW is about 1.341022 hp. This is the reverse of horsepower to kilowatts.
- Megawatts to Kilowatts Convert megawatts to kilowatts. One megawatt is 1000 kilowatts exactly. Mechanical horsepower is on the same list. This is power, not megawatt-hours of energy.
- Power Converter Convert power units with fixed factors. Nothing uploaded.
- Bar to PSI Convert bar to pound-force per square inch. One bar is exactly 100000 Pa. One PSI is 6894.757293168 Pa. This page does not add atmospheric pressure.
- Pressure Converter Convert a pressure number between pascals, kilopascals, bar, PSI, standard atmospheres, and torr. This page does not add or subtract atmospheric pressure, and it is not a weather station.
- PSI to Bar Convert pound-force per square inch to bar. One PSI is 6894.757293168 Pa. One bar is 100000 Pa. This is the reverse of bar to PSI and does not add atmosphere.
- Angle Converter Convert plane angles among degrees, radians, gradians, and turns. The browser uses Math.PI. A percent grade is a slope ratio, not a unit on this list.
- Decimal Degrees to DMS Converter Switch between decimal degrees and degrees-minutes-seconds (DMS). Default direction splits 30.5° into 30° 30' 0". Reverse direction rebuilds a decimal from D, M, and S.
- Time Units Converter Convert a duration among milliseconds, seconds, minutes, hours, days, and weeks. A day is 86400 SI seconds. This is not a calendar, a time zone, or a Unix timestamp.
- Cooking Converter Convert US kitchen volume: teaspoons, tablespoons, cups, fluid ounces, milliliters, liters, and US gallons. This is not an imperial cup and it does not weigh flour.
- Fuel Economy Converter Convert US miles per gallon into liters per 100 km. These two units move in opposite directions: a higher mpg is a lower L/100 km. This page is not a fuel cost calculator.
- Force Converter Convert a force between newtons, kilonewtons, pound-force, kilogram-force, and dynes. One pound-force is 4.4482216152605 N. This is force, not mass and not torque.
- Frequency Converter Convert a frequency between hertz, kilohertz, megahertz, gigahertz, and revolutions per minute. One rpm is 1/60 hertz. This page does not compute wavelength.
- Torque Converter Convert a torque between newton-meters, kilonewton-meters, pound-force feet, pound-force inches, ounce-force inches, and kilogram-force meters. One lbf·ft is 1.3558179483314004 N·m. Torque is not a stored energy in joules.