Use this calculator to figure how much your current savings will grow and how much more you'll need to save each month in order to achieve a given savings goal within a given number of years. Start with Line 1 and enter your future savings goal. 1. Savings Goal. Instructions 2. Current savings balance. 3. Annual percentage rate (APR). 4. Number of years. Explanations 5. Current savings future value (FV). 6. Total savings gap. 7. Monthly deposit required.