Enter the measured value and the true value into the calculator to determine the percent deviation.

Percent Deviation Formula

The following formula is used to calculate a percent deviation.

D =( Xm – Xt ) / Xt * 100

  • Where D is the percent deviation (%)
  • Xm is the measured value
  • Xt is the true value

Percent Deviation Definition

A percent deviation is defined as the percentage difference between a measured value and a true value.

Percent Deviation Example

How to calculate percent deviation?

  1. First, determine the measured value.

    Take the measured value measurement.

  2. Next, determine the true value.

    Calculate the theoretical true value.

  3. Finally, calculate the percent deviation.

    Calculate the percent deviation using the formula above.


What is a percent deviation?

A percent deviation is the variance of a given value from a known true value presented as a ratio of the percentage of the true value.

percent deviation calculator
percent deviation formula