Chemistry
Percent difference
Used when neither figure is authoritative. Dividing by the midpoint keeps the result symmetric in the two values.
The Formula
percent difference = |E - T| / ((|E| + |T|) / 2) x 100
Used when neither figure is authoritative. Dividing by the midpoint keeps the result symmetric in the two values.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| E | First value | any unit | One of the two measurements being compared. |
| T | Second value | same unit | The other measurement. Neither is treated as true. |
What Each Symbol Means
Eany unit
First value
One of the two measurements being compared.
Tsame unit
Second value
The other measurement. Neither is treated as true.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate percent error page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate Percent Error, filed under Science. Every number the guide produces comes from substituting into this one line.