Why does percentage error use the accepted value in the denominator?
Because the accepted value is the reference point. The calculation asks how large the measurement miss is relative to the value you were trying to match.
Percentage Error Calculator
Compare a measured value with an accepted reference value by making absolute error visible first, then converting that error into a relative percentage.
Measured value, accepted value, and the miss between them
Percentage error is useful in lab reports, calibration checks, batch targets, and inspection readings. It asks how large the measurement miss is relative to the value you were trying to match.
Calculate percentage error
- Enter the measured value.
- Enter the accepted value.
- Confirm both values use the same units.
- Review absolute error.
- Interpret the percentage error.
Loading tool...
From absolute error to percent error
The accepted value is the reference denominator, so zero or near-zero references need special care.
Absolute error
Relative error
Percentage error
Direct formula
Signed diagnostic
When the accepted value is zero or tiny
- Percentage error is undefined when the accepted value is zero.
- Near zero, small absolute misses can become huge percentages.
- Use absolute error, signed error, or a domain tolerance when relative percent is misleading.
FAQ
What should I use if the accepted value is zero?
Percentage error is undefined when the accepted value is zero. Use absolute error, signed error, or a domain-specific tolerance instead.
