Absolute Error
Definition and meaning of Absolute Error in chemistry.
Absolute error is the difference between a measured value and the true or accepted value of a quantity. It is reported in the same units as the measurement and shows how far a result lies from the correct value.
In more detail
Absolute error is calculated as the measured value minus the true value, and its size indicates the accuracy of a measurement. Because it keeps the original units, it does not by itself show whether an error is large relative to the quantity measured, that is the job of relative error, which expresses the same difference as a fraction or percentage.
Key facts
| Definition | Measured value − true value |
|---|---|
| Units | Same as the measurement |
| Indicates | Accuracy |
| Field | Analytical chemistry |
If a balance reads 9.8 g for an object whose true mass is 10.0 g, the absolute error is −0.2 g.
Frequently asked questions
What is the difference between absolute and relative error?
Absolute error is the plain difference between measured and true values, in the original units. Relative error expresses that difference as a fraction or percentage of the true value.