Relative Standard Deviation Calculator
Calculate relative standard deviation (coefficient of variation) — standard deviation as a percentage of the mean.
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Relative Std Dev (%RSD)
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Mean
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Standard Deviation
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Coefficient of Variation
Recent Calculations
What Is Relative Standard Deviation?
Relative Standard Deviation (RSD), also called Coefficient of Variation (CV), expresses standard deviation as a percentage of the mean. It allows comparing variability between datasets with different units or scales.
Formula
%RSD = (σ / |μ|) × 100Example
For {10, 12, 11, 13, 9}: Mean = 11, SD = 1.414, RSD = 12.86%.
Frequently Asked Questions
When is RSD useful?
RSD is used to compare variability between datasets with different means or units. In chemistry, RSD < 5% often indicates good precision.
RSD vs standard deviation?
SD is in the same units as the data. RSD is dimensionless (a percentage), making it easier to compare across different measurements.