Unit converters
Canadian life mixes metric and imperial every day: a forecast in Celsius and a US oven in Fahrenheit, fuel in litres and a tank in gallons, a height in centimetres and a bed in feet. These converters use the exact definitions published by NIST, show the common values and run in your browser.
Centimetres to inches
Convert centimetres to inches and back with the exact factor, a table of common values and no sign-up.
Millimetres to inches
Convert millimetres to inches and back with the exact factor, a table of common values and no sign-up.
Feet to metres
Convert feet to metres and back with the exact factor, a table of common values and no sign-up.
Kilometres to miles
Convert kilometres to miles and back with the exact factor, a table of common values and no sign-up.
Kilograms to pounds
Convert kilograms to pounds and back with the exact factor, a table of common values and no sign-up.
Kilograms to stone
Convert kilograms to stone and back with the exact factor, a table of common values and no sign-up.
Litres to US gallons
Convert litres to US gallons and back with the exact factor, a table of common values and no sign-up.
Litres to imperial gallons
Convert litres to imperial gallons and back with the exact factor, a table of common values and no sign-up.
Square feet to square metres
Convert square feet to square metres and back with the exact factor, a table of common values and no sign-up.
Hectares to acres
Convert hectares to acres and back with the exact factor, a table of common values and no sign-up.
km/h to mph
Convert kilometres per hour to miles per hour and back with the exact factor, a table of common values and no sign-up.
kPa to psi
Convert kilopascals to pounds per square inch and back with the exact factor, a table of common values and no sign-up.
Celsius to Fahrenheit
Convert °C to °F and °F to °C with the exact formulas, plus a table of weather, body, oven and freezer temperatures.
Height converter
Convert a height from centimetres to feet and inches, or from feet and inches to centimetres, with a table of common heights.
Unit converter
Pick a quantity, choose two units and type a value. You also see every other unit of that quantity at once.
File size converter
Type a size, choose the units and see it in bytes, kilobytes, megabytes, gigabytes and terabytes, in both the 1,000 and the 1,024 system.
How to choose the right tool
Use the single-purpose converters when you know the two units: centimetres or millimetres to inches, feet to metres, kilometres to miles, kilograms to pounds or stone, litres to US or imperial gallons, square feet to square metres, hectares to acres, km/h to mph, kPa to psi, Celsius to Fahrenheit and file sizes. The general unit converter handles many more units in one place, and the height converter writes a height in feet and inches.
Accuracy, sources and privacy
Conversions use exact or internationally agreed factors: 1 inch is exactly 2.54 centimetres, 1 pound is exactly 0.45359237 kilograms, and the imperial and US gallons are treated as different units, which matters in Canada. Results are shown with sensible rounding and can be copied as typed. Everything on these pages runs in your browser. What you type is not sent to a server, not stored by us and not added to the web address.
Questions about unit converters
Are US and imperial gallons the same?
No. An imperial gallon is about 4.546 litres and a US gallon about 3.785 litres. Canadian fuel economy in mpg often means imperial gallons, so the difference is large.
How exact are the conversions?
They use exact definitions where they exist, such as 2.54 cm per inch, and standard factors otherwise, with the rounding shown.
Which units are used in Canada?
Canada is officially metric, but feet, inches and pounds are common for height, weight and construction, which is why metric and imperial are both here.
Can I convert in either direction?
Yes. Each converter works both ways.
Questions about unit converters
Are US and imperial gallons the same?
No. An imperial gallon is about 4.546 litres and a US gallon about 3.785 litres. Canadian fuel economy in mpg often means imperial gallons, so the difference is large.
How exact are the conversions?
They use exact definitions where they exist, such as 2.54 cm per inch, and standard factors otherwise, with the rounding shown.
Which units are used in Canada?
Canada is officially metric, but feet, inches and pounds are common for height, weight and construction, which is why metric and imperial are both here.
Can I convert in either direction?
Yes. Each converter works both ways.
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