What is the percent error and how do you calculate it?

The percent error defines the difference between the estimated values and the actual value and the difference is described in the form of a percentage. In the percent error, the percent error is multiplied by 100. The percent error calculator makes it possible to find how large our error is when we are measuring or the analysis of the process. The smaller percentage tells us we are close to the real value. The best percent error calculator makes it possible to determine that we are able to find the actual value. In the percent error, we actually deduct the estimated values by the actual value and divide them by the actual value. The result is multiplied by 100, and the percentage error calculator makes the task easy for the scientist and analysts.

The percent error formula:

The Formula for the percent error of can be produced by taking the mode of the estimated values and subtracting them from the actual values. Then we need to multiply the result by 100 to convert to the percentage.

Percent Error= PE = (|Estimated value-Actual value|/ Actual value) × 100

Or or we can write the formula as

% Error =T-ET× 100


T = True or actual value 

E = Estimated value 

You can use the explore percentage error calculator to find the percentage error of the observation and our experiments.

Why are percent errors unavoidable?

1% error means that we got very close to the accepted value. On the other hand, 48% means that we are away from the true value. Estimation errors are sometimes unavoidable due to certain reasons

  • Hands can be shaken or measurement can be taken exactly
  • material can have measurement error
  • our instruments do not have the capability to estimate exactly.

The percentage error calculator makes it possible to avoid the error in our estimation and we can calculate the specific measurements.

Example of percent error:

A man measured the area of a certain rectangular plot of 468 cm2.On the other hand, the actual area of the plot recorded is  470 cm2.Find the percent error.


Estimated value = 468 cm2

Actual value = 470 cm2

Percent Error= PE = (|Estimated value-Actual value|/ Actual value) × 100

% Error =T-ET× 100

Now by adding the value in the percent error calculator, then we have the percent error:

Percent Error= PE = (|468-470|/ 470) × 100

Percent Error= PE = (|-2|/ 470) × 100

Percent Error= PE = 0.43 %

Percent example 2:

A businessman started a business on 1 first of January. Based on the demand of the certain area,he expected a certain number of people or clients to visit his store each month.The table below gives the information on the number of visitors for the shop during the first quarter. When added to the percent error calculator, we can estimate the following demand.

MonthThe expected consumer in the store Number of consumer visited 


MonthDifference (ignoring the sign)Relative errorPercent error
January500.11110.1111 × 100 = 11.11%
February1000.20.2 × 100 = 20%
March300.050.05 × 100 = 5%

Mean percent error = (11.11% + 20% + 5%)/ 3

= 36.11%/3

=12.0367% (approx)


The percent error calculator is used to determine how close we are to the actual estimation. It is used to determine how we are performing to the actual value. The whole idea is to keep the record close to the expected values when doing business or doing any kind of experiment.


Kate Johnson is a content writer, who has worked for various websites. She is also a college graduate who has a B.A in Journalism.

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