RSD Calculator

Relative Standard Deviation (RSD) is a statistical comparison of how far a data point diverges from the mean. It is important in the lab and analysis of data to determine consistency and precision. The RSD formula is:RSD (%) = Standard Deviation ÷ Mean × 100 This formula is also called the percent RSD calculation formula. Because the formula is frequently in use and involves multiple data points, many people use an RSD calculator for fast calculations, and some people use an RSD Percent Excel spreadsheet.

To calculate RSD in Excel, you must first organize your data in a column. Then, for standard deviation in Excel, you can use either =STDEV.P(range) or =STDEV.S(range), and for average, you can use =AVERAGE(range). Then, you can use the RSD calculation formula in Excel, where you would use, *=(STDEV(range)/AVERAGE(range)) * 100 In the example of data points of 10, 12, 11, 13, and 12, you would find the mean to be 11.6, and the standard deviation to be approximately 1.14. Then, to use the formula, RSD = approximately (1.14 ÷ 11.6) × 100, so RSD = approximately 9.83. This is showing the divergency of data as a percentage.

As an example calculation, the same data points of 10, 12, 11, 13, and 12 can be easily input into a calculator to find the mean and the standard deviation to make the calculation faster. Also, many apps and some downloadable RSD calculator tools make the calculations even easier. Most importantly, RSD is a calculation of data reliableness, as in analysis or experiments, varies, that RSD helps show the comparison and how precise.