

No single conversion factor can be used to convert temperatures in the English system (degrees Fahrenheit or degrees Rankine) to temperatures in the SI system (degrees Celsius and degrees Kelvin) or the other way around. Use of these prefixes avoids the need for powers of 10 notations. SI prefixes indicating orders of magnitude are provided in Table 2. Additional conversion factors are presented for energy, energy density, and energy yields. Table 1 presents the conversion multiplication factors to convert from English units to SI units (and vice versa) for basic measurements including length, weight, area, volume, bulk density, mass flow rate, volume flow rate, pressure and power. The fact sheet is intended for use in the classroom as well as for extension outreach programs.

This fact sheet is intended to serve as a reference for converting many different types of measurements quickly and accurately from one system of units to another. The conversion factors presented are for general measurements as well as those primarily associated with energy calculations additional conversion multipliers can be found in the the references. Unit conversion multipliers are presented in this fact sheet along with several examples to describe the use of these multipliers. There have been some very costly failures associated with insufficient attention being given to the units of measurements involved in calculations and communications.Ī methodical approach is needed to avoid errors encountered when converting from one system of units to another. World-wide communications, commerce, finance and many other functions depend upon everyone involved in the processes to be knowledgeable of both systems of measurements. As our society and economy become more global in scope, it is increasingly important to fully comprehend both the English and the SI systems of units and to accurately and conveniently convert from one system to another.

The SI system of units (often referred to as the metric system) is the official system for measurements in nearly all countries of the world, but not in the U.S. Today it is very important to be able to understand measurements in both the English system of units and the SI (Systems International) system of units.
