Select the appropriate unit options and then enter your number in any field of this PPM calculator and get the converted value.
Parts-Per Notation
The parts-per notation is a set of pseudo-units to describe small values of various dimensionless quantities, e.g. mole fraction or mass fraction. These fractions, being measures of quantity-per-quantity, are dimensionless because they represent the ratio of parts of the same nature.
Commonly used parts-per expressions are:
• Percent (%) is one part per hundred and denotes a value of 10−2.
• Permille (‰) is one part per thousand and denotes a value of 10−3.
• One part per million (PPM) denotes a value of 10−6.
• One part per billion (PPB) denotes a value of 10−9.
• One part per trillion (PPT) denotes a value of 10−12.
Any conversion involving these units is easily done with our PPM calculator.
In chemistry, parts-per notation is often used to describe highly dilute solutions. For example, the relative content of dissolved minerals or pollutants in water is indicated in this way. So, the quantity “1 ppm” can be used to indicate the mass fraction of a solute if the solute is present in the water in an amount of one millionth of a gram per gram of the sample solution.
Similarly, in physics and engineering, the parts-per notation is used to express the meaning of various proportional quantities. For example, a metal might expand 1.2 micrometers per meter of length for every degree Celsius and this would be expressed as a coefficient of thermal expansion of 1.2 ppm/°C.
In nuclear magnetic resonance spectroscopy, chemical shift is usually expressed in PPM. It represents the difference of a measured frequency in parts per million from the reference frequency.
Note, that the parts-per notation is not formally a part of the International System of Units (SI). The International Bureau of Weights and Measures recognizes the use of parts-per notation, but suggests avoiding the use of PPB and PPT to avoid misunderstandings.