Savings Calculator
Planning a savings goal
Estimate how an opening balance and end-of-month deposits may grow at a constant annual interest rate. The calculator separates your deposits from estimated interest so you can see how much of the final balance comes from each.
Formula and method
Future value combines compound growth on the initial amount with the future value of a monthly ordinary annuity.
Worked example
$5,000 plus $500 per month for 10 years at 4% grows to roughly $80,900, assuming the rate remains constant.
How to interpret the result
Compare total deposits with estimated interest to see whether the goal depends mostly on saving behavior or on growth assumptions. Monthly deposits are placed at the end of each month. Depositing at the beginning would produce a slightly higher balance because every contribution earns one additional month of interest.
Important limitations
- Bank rates can change and deposit timing matters.
- Inflation and taxes are not included.
Common questions
Should I enter APY or an interest rate?
Use a rate that matches the calculator's monthly compounding assumption. A bank's APY already reflects compounding, so converting between nominal rate and APY may be necessary for a precise comparison.
Why will a real account differ?
Rates can change, deposit dates vary, interest may be rounded daily or monthly, and taxes can reduce retained earnings. Treat the projection as a planning scenario, not an account statement.
Related tools
Method and examples reviewed September 8, 2026.