Percent Error Calculator - Calculator See


Percent Error Calculator

Calculate percent error, absolute error, and relative error between experimental laboratory measurements and true theoretical values.

Calculator Inputs

Measurement recorded in lab or test.
Standard true reference value.

Calculated Results

Percent Error
4.25%
Absolute Error 0.42 Units
Relative Error 0.0425
Measurement Accuracy 95.75%
Values calculate live as you adjust inputs.

About Percent Error Calculator

Percent error evaluates the precision and accuracy of experimental scientific measurements by comparing observed results against established standard values.

What is Percent Error Calculator?

Percent error evaluates the precision and accuracy of experimental scientific measurements by comparing observed results against established standard values.

How to Use This Calculator

  1. Enter the experimental measurement recorded.
  2. Enter the accepted theoretical or standard textbook value.
  3. Review percentage error and overall measurement accuracy percentage.

The Mathematical Formula & Variables

Percent Error = (|Experimental - Theoretical| / |Theoretical|) * 100

Variables Definition

Symbol / Variable Name Description
|E - T| Absolute Error Magnitude of discrepancy between observed and actual.

Step-by-Step Worked Example

Scenario: Measured gravitational acceleration at 9.42 m/s² against true standard 9.84 m/s².

  1. Absolute error = |9.42 - 9.84| = 0.42.
  2. Divide by theoretical = 0.42 / 9.84 = 0.04268.
  3. Multiply by 100 = 4.27% error.

Result: Percent Error = 4.27%

Frequently Asked Questions

Can percent error be negative?

Traditionally, percent error uses absolute values so the result is always positive. When absolute value is omitted, a negative error indicates the measured value was lower than expected.