Uncertainty measures the lack of certainty or sureness of an outcome.
Uncertainty of a measured value can also be presented as a percent or as a simple ratio.
Formula to calculate percent uncertainty.
When calculating percent uncertainty, absolute uncertainty is used.
![Calculate Percent Uncertainty.](https://www.learntocalculate.com/wp-content/uploads/2021/02/percent-uncertainty.png)
Example:
Suppose you measured the quantity of a solution using a measuring cylinder and found it to be 25.2 cubic centimeters, if the uncertainty value is ± 0.05, calculate the percent uncertainty.
![Calculate Percent Uncertainty.](https://www.learntocalculate.com/wp-content/uploads/2021/02/percent-uncertainty-2.png)
Therefore, the percent uncertainty is 0.2%.