How to use the savings goal calculator
- Pick a mode. How much to save monthly? finds the deposit that hits your goal by a deadline. When will I reach my goal? finds the finish date for a deposit you already make.
- Enter your Savings goal and your Current savings, the money already set aside for this goal.
- Enter the Annual interest rate your account pays. Use 0 if the money sits in checking.
- Enter a Time frame in months or years, or your Monthly deposit in the second mode. Results update as you type.
- Open Growth timeline to see the balance by month or by quarter.
How the calculation works
Interest compounds monthly at the annual rate divided by 12, and each deposit is added at the end of the month. The monthly deposit comes from the future value of an ordinary annuity, solved for the payment:
Deposit = (Goal − Current × (1 + i)n) × i ÷ ((1 + i)n − 1)
Here i is the monthly rate and n is the number of months. At a 0% rate the deposit is simply (Goal − Current) ÷ n. The second mode adds interest and your deposit one month at a time until the balance reaches the goal. The same compounding math runs the SEC's Investor.gov compound interest calculator. To see how a balance grows with no target in mind, try the savings interest calculator.
Worked example
The default inputs are a $10,000 goal, $1,000 already saved, 4.5% interest and 24 months. The monthly rate is 0.375%, and your $1,000 grows to about $1,094 alone, so deposits cover the rest. The tool shows $355.33 a month. Over 24 months you deposit $9,527.93 in total (counting your starting $1,000) and earn $472.07 in interest, 4.7% of the final $10,000. The milestone cards show 25% of the goal in month 5, 50% in month 11 and 75% in month 18.
Limits and edge cases
- Rate vs APY. The rate field is a yearly rate compounded monthly. A bank quoting 4.50% APY pays about 4.41% compounded monthly, so enter 4.41 for an exact match.
- Taxes, fees and inflation are not subtracted. Savings interest is taxable income, so the real balance can be a little lower.
- Variable rates. Savings rates change, so rerun the plan when yours does.
- If your savings already meet the goal, or interest alone will get you there before the deadline, the tool says so and the deposit is $0. The second mode stops at 100 years.
Frequently asked questions
How much should I save each month?
Enough to reach each goal by its date, which is what the first mode calculates. The 50/30/20 guideline puts about 20% of after-tax pay toward savings and extra debt payments. If your goals add up to more, stretch a deadline or trim a goal.
Does it matter if I deposit at the start of the month?
A little. This calculator assumes end-of-month deposits. Depositing at the start of each month earns one extra month of interest on every deposit, so with the default inputs you would need $354.00 a month instead of $355.33.
Should I keep goal money in savings or invest it?
For goals under about three years away, an FDIC-insured savings account or CD protects your principal. For goals five or more years out, investing may grow faster but can lose value right when you need the money, so plan with a conservative rate.
What interest rate should I enter?
Enter the rate your account pays today. Online high-yield savings accounts often pay several times the national average savings rate, which the FDIC publishes on its national rates page. If your bank quotes an APY, see the rate vs APY note above.
Planning a cushion before other goals? The emergency fund calculator sizes it from your monthly expenses, and the compound interest calculator projects longer-term growth.
Sources: SEC Investor.gov, Compound Interest Calculator; FDIC, National Rates and Rate Caps. Results are estimates for planning, not financial advice.