Support: Unit Converter

Tell us what happened. Include which page you were on and what you expected to see. Most answers go out within a business day.

Common questions

How many centimeters are in an inch?

Exactly 2.54. Since 1959 the inch has been defined as 2.54 cm, so 10 inches is 25.4 cm and 10 cm is 3.937 inches.

How do I convert kg to lbs?

Multiply by 2.20462: 70 kg is 154.32 lb, or 154 lb 5.2 oz. A pound is exactly 0.45359237 kg.

What is the formula for Celsius to Fahrenheit?

Multiply by 9/5 and add 32. 0 °C is 32 °F, 20 °C is 68 °F, 37 °C is 98.6 °F and 100 °C is 212 °F.

How tall is 5 feet 7 inches in cm?

Choose Length, set feet to centimeters and type 5'7" or 5 ft 7 in: it is 170.18 cm.

How many mL are in a fluid ounce?

A US fluid ounce is 29.5735 mL and a UK fluid ounce 28.4131 mL. A US cup of 8 fluid ounces is 236.6 mL.

Is a US gallon the same as a UK gallon?

No. A US gallon is 3.785 liters and a UK (imperial) gallon 4.546 liters. Both are listed so you can pick the one your recipe or label uses.

Where do the factors come from?

They are the exact definitions published by NIST, the US National Institute of Standards and Technology, in its guide to SI units and Handbook 44: the international inch, pound and gallon definitions.

Is anything sent anywhere?

No. The conversion runs in your browser and nothing you type is sent to us or stored.