Percent Error Calculator
Check how accurate an experiment was. Enter your measured value and the accepted true value to get the absolute error and the percent error instantly — a standard step in lab reports and science homework.
Enter the values — the result will show live here.
How to use
- Write your measured (experimental) value.
- Write the actual value from your book or the standard.
- The result will show both percent error and absolute error.
Note: Formula: percent error = (|experimental - actual| / |actual|) x 100. If the actual value is zero, percent error cannot be found.
Tips
- Percent error is always positive — it measures the size of the error, not its direction.
- Take the 'actual' value from your textbook or an accepted standard, not from another guess.
- A small percent error means your experiment was close to the accepted value.