PPM Calculator
If percentages, per mille, and parts per million still confuse you, give this PPM calculator a shot. It is a simple tool that can be used for conversion from PPM to units such as percent or parts per billion (PPB). In this article, we will provide you with a short description of each proportion metric and give you a detailed explanation of how to calculate PPM and percentages.
How to calculate PPM and percents
All of the proportion metrics are quite similar: they describe small values of dimensionless quantities, such as the volumetric proportion of $\text{NO}_2$ in the air. For example, PPM means "parts per million". If you find out that the concentration of $\text{NO}_2$ is equal to 1 ppm, it means that if you take a "sample" of air and divide it into a million parts, one of them will consist of $\text{NO}_2$.
The proportion metrics are as follows:
 Percentage: equal to 1 per 100;
 Per mille: equal to 1 per 1,000;
 PPM: equal to 1 per 1,000,000;
 PPB: equal to 1 per 1,000,000,000; and
 PPT: equal to 1 per 1,000,000,000,000.
💡 For more info on proportions, please see our dedicated proportion calculator.
PPM conversion: an example
Let's take the following example: you have created a solution of salt ($\text{NaCl}$) in water. You used 0.005 grams of salt, and the final mass of the solution is equal to 1 kilogram. How many parts per million (PPM) of salt are in the solution?
 Start with expressing the solution concentration as a decimal. There are 0.005 grams of salt in 1 kilogram (1000 grams). It means that the decimal is equal to
 To find the percentage, multiply this value by a hundred:
 To find the per mille value, multiply the decimal by a thousand:
 For the PPM, multiply the decimal by a million:
 Finally, for the PPB, multiply the decimal by a billion:
One of the applications of such PPM calculations in everyday life is finding and adjusting your swimming pool's salinity. We have a salinity calculator that can help you get it just right.
💡 Check out our solution dilution calculator for all your solution dilution needs.
What are PPMs?
PPMs or parts per million are a unit of measurement of concentration. A part per million corresponds to a concentration of one part of a substance per 999,999
parts of solvent, out of a total of one million. PPM are scientific units used to compare quantities with the same measurement units (moles, square meters, ...).
What are PPM of CO₂?
Climatologists measure the concentration of carbon dioxide in the atmosphere using the parts per million. As of 2022, there are 414 PPM of CO₂ in the atmosphere. This means that for every million gas molecules in the atmosphere, 414 are carbon dioxide. In 2002 this number was 373, and before the industrial revolution, around 285.
How do I calculate the PPM from the percentage?
To calculate the parts per million from the percentage, multiply the value in percent by 10,000
. For example, in the case of a concentration of 0.12%
, the corresponding parts per million are:
0.12 × 10,000 = 1,200
.
How do I convert in the parts per notation?
To convert concentrations in the parts per notation, follow the next few steps:

From your number...

Multiply by
100
to find the percentage (part per 100); 
Multiply by
1,000
to find the per mille (or multiply the percentage by 10); 
Multiply by
1,000,000
to find the parts per million (PPM), or multiply the per mille by1000
, or the percentage by10,000
; 
Multiply by
1,000,000,000
to find the parts per billion (PPB); 
Multiply by
1,000,000,000,000
to find the parts per trillion (PPT).
How many ppm is a 0.05% bleach solution?
500 PPM. To calculate the PPM from the percentage, simply multiply the value in percent by 10,000
:
PPM = % × 10,000
0.05 × 10,000 = 500
This concentration of bleach is suitable for disinfection: if you need to sanitize a surface, prepare it, but be careful doing so!