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FAQ
How accurate are the conversions?
Our conversions use scientifically accurate formulas and conversion factors. For most everyday purposes, the precision is more than sufficient. For scientific applications, we use the internationally standardized SI unit definitions.
What is the difference between metric and imperial units?
The metric system (SI) is based on powers of 10 and is used in most countries worldwide. The imperial system originated in Britain and is still primarily used in the USA. Metric uses meters, kilograms, and liters, while imperial uses feet, pounds, and gallons.
Who invented the metric system?
The metric system was developed during the French Revolution in the 1790s by the French Academy of Sciences. It was designed to be a universal, decimal-based measurement system. The meter was originally defined as one ten-millionth of the distance from the equator to the North Pole.
Why are there different temperature scales?
Different temperature scales were developed independently by scientists in different countries. Fahrenheit (1724) was developed in Germany, Celsius (1742) in Sweden, and Kelvin (1848) in Scotland. Celsius and Kelvin are metric-based, while Fahrenheit remains popular in the USA.