Calculation of Error
In experimental science, there is no exact measurement. Measurements are subject to more or less significant errors depending on the quality of the instruments and the skill of the experimenter.
• A discrepancy exists between the obtained value and the exact value, which remains unknown.
• This discrepancy is referred to as "measurement error."
• The true value remaining unknown.
• The measurement error will remain undetermined.
The absolute error and the relative error:
In practice, errors can only be estimated there are two types of errors:
The absolute error
The absolute error represents the mathematical quantity that measures the difference between the measured or observed value of a quantity and its true or theoretical value. It is calculated by taking the absolute value of the difference between these two values. The general formula for absolute error (Eabs ) is as follows:

This measure allows the assessment of the overall discrepancy between the experimental measurement and the expected value, irrespective of the direction of this difference. The absolute error is a crucial tool in the analysis of experimental results and helps quantify the accuracy of the measurements taken.
the relative error
I provided the general formula for relative error in the previous response. If you have specific values for the approximate value and true value, you can plug them into the formula to calculate the relative error.
To reiterate:

And if you want the result as a percentage:

Uncertainty calculations
For a quantity g=f(x,y,z), its total differential is expressed as:

The absolute uncertainty on the variable g is obtained by considering the variations in the variables that compose it, namely:
