Select any unit of measure with the calculator to determine the greatest possible error of that unit.

Greatest Possible Error Formula

The following formula is used to calculate the greatest possible error.

GPE = U * .5
  • Where GPE is the greatest possible error
  • U is the units (i.e, inches, cm, m)

To calculate the greatest possible error, multiply the units by one half.

What is the greatest possible error?


The greatest possible error is a measure of how much error could be seen in a measurement, based on the units being measured.

In more exact terms, the greatest possible error is 1/2 of the units of measure being used. For example, if the units of measure are inches, the greatest possible error is (1/2) = .5 inches.

How to calculate greatest possible error?

Example Problem:

The following example outlines the steps required to calculate the greatest possible error.

For this example, we want to find the greatest possible error in cm.

First, determine the units of measure that are going to be used to measure the object. In this case, the units are inches.

Next, determine the GPE in inches. The GPE is always half of the measurement unit, so GPE = .5 inches.

Finally, convert into terms of centimeters by multiplying the result by 2.54.

GPE = .5 * 2.54

GPE = 1.27 cm