Here is the electrostatic energy stored in capacitor formula to calculate the energy stored in a capacitor. Electric charge and the capacitance are the inputs needed by this electric potential energy stored in a capacitor formula to perform calculations. Just replace the variables in the formula with its respective values and do the operations as guided by the formula to get the results. For capacitance, you can use the values in units like farad, picofarad, nanofarad etc.
Refer this electrostatic energy stored in capacitor formula to do the potential energy calculation on your own. As per the formula, just divide the squared electric charge value with the product of capacitance and integer 2 to get the result.