Please see "Examples" page for a detailed explanation of this calculator. This calculator lets you calculate for either spike volume or spike analyte quantity as percent of sample analyte weight. The required values are as given in the table. The input cells with green outline means leave the value to be calculated blank and fill out the other input cell. All input cells with brown outline must be filled out (see "Examples" page). The final volume is the total of the sample volume and spike volume. The total final analyte concentration that is calculated here is the theoretical value or the value you would get if you have 100% spike recovery. Use the actual total final analyte concentration that is determined by the analysis method to calculate the percent spike recovery in a separate calculator in this set called the Analytical Spike Recovery Calculator. The picture here is for illustration purposes only, the final solution should be homogeneous. Check out also the Analytical Spike Addition Calculator with Solvent Addition.