Savings Calculator
See how your savings grow with regular contributions and compound interest.
Year-by-Year Growth
| Year | Start Balance | Contributions | Interest | End Balance |
|---|
What is a Savings Calculator?
A savings calculator projects how much money you will have in the future based on your initial deposit, regular contributions, interest rate, and time. It demonstrates the power of compound interest: as your balance grows, you earn interest on your interest, so growth accelerates the longer you leave the money untouched.
Use it to model an emergency fund, a down payment, a vacation fund, or any other goal. Enter your numbers above to see your projected balance, total contributions, interest earned, and a year-by-year growth table — all calculated locally in your browser.
How Savings Grow: The Formulas
Your ending balance is the sum of two parts: compound interest on the initial deposit, plus the future value of your regular contributions. The initial deposit follows the classic compound interest formula: FV = P(1 + r/n)^(nt)
Regular contributions follow the future value of an ordinary annuity — each deposit compounds for the time it stays in the account: FV = C × [((1 + r/n)^(nt) − 1) / (r/n)]
- FV — future value: what your money is worth at the end
- P — principal: your initial deposit
- C — contribution per compounding period. This calculator spreads your monthly deposit evenly across periods, so C = monthly contribution × 12 / n
- r — annual interest rate as a decimal (4.5% becomes 0.045)
- n — compounding periods per year: 12 monthly, 4 quarterly, 1 yearly, 365 daily
- t — time the money stays invested, in years
Deposits are assumed at the end of each period, and your ending balance is the two results added together.
Worked Example: $5,000 Up Front Plus $200 a Month
Suppose you deposit $5,000, add $200 every month, and earn a 4.5% annual rate compounded monthly for 10 years. Then r/n = 0.045/12 = 0.00375, nt = 120, and the growth factor (1.00375)^120 ≈ 1.566993.
- Initial deposit:
5,000 × 1.566993 ≈ $7,834.96 - Monthly contributions:
200 × (1.566993 − 1) / 0.00375 ≈ $30,239.61
Your final balance is $38,074.58. You contributed $29,000.00 out of pocket ($5,000 plus 120 deposits of $200), so the remaining $9,074.58 is interest the account paid you. Compounding picks up speed over time: the account earns about $280 of interest in year 1 but roughly $1,615 in year 10.
Reference Table: $200 a Month at Different Rates
Ending balances for $200 per month with no initial deposit, compounded monthly with deposits at month-end — exactly how the calculator above computes it.
| Years | Total Contributed | 2% Rate | 4% Rate | 5% Rate | 6% Rate |
|---|---|---|---|---|---|
| 5 | $12,000 | $12,609.47 | $13,259.80 | $13,601.22 | $13,954.01 |
| 10 | $24,000 | $26,543.93 | $29,449.96 | $31,056.46 | $32,775.87 |
| 20 | $48,000 | $58,959.37 | $73,354.93 | $82,206.73 | $92,408.18 |
| 30 | $72,000 | $98,545.08 | $138,809.88 | $166,451.73 | $200,903.01 |
At 6% for 30 years you deposit $72,000 and end with $200,903.01 — nearly two-thirds of the final balance is interest. Time in the account matters more than chasing a slightly higher rate.
APY vs. APR: What's the Difference?
APR (annual percentage rate) is the nominal annual rate before compounding; APY (annual percentage yield) is what you actually earn over a year once compounding is included. The conversion is APY = (1 + r/n)^n − 1, where r is the nominal rate and n the compounding periods per year.
A 4.50% nominal rate compounded monthly works out to (1 + 0.045/12)^12 − 1 ≈ 4.594% APY. Banks quote APY so you can compare accounts apples-to-apples regardless of compounding schedule; lenders quote APR on loans — our APR calculator turns loan rates and fees into an effective annual cost.
Where to Keep Your Savings
Emergency Fund: Three to Six Months of Expenses
Before chasing returns, build an emergency fund of three to six months of essential living expenses. If your essentials run $4,000 a month, that is a target of $12,000 to $24,000. Aim for the three-month end with a stable job and dual incomes, and the six-month end or more if you are self-employed, work on commission, or rely on one paycheck. A budget calculator can help pin down your true monthly essentials.
High-Yield Savings Accounts
High-yield savings accounts, usually offered by online banks, pay many times the national average rate of traditional banks while remaining FDIC insured up to $250,000 per depositor, per institution (NCUA covers credit unions on the same terms). Rates are variable, but the mix of liquidity, safety, and yield makes them the default home for emergency funds and short-term goals.
CD Ladders
Certificates of deposit pay a fixed, typically higher rate in exchange for locking up your money for a set term. A CD ladder softens that trade-off: split your savings across CDs maturing one through five years out, and as each rung matures, reinvest it in a new five-year CD. Most of your money earns long-term rates while a rung still comes due every year. Model the returns with our CD calculator.
How to Use This Calculator
- Enter your starting balance and how much you plan to contribute each month.
- Enter the annual interest rate you expect to earn and the number of years.
- Select how often interest compounds: monthly, quarterly, yearly, or daily.
- Click Calculate to see your future balance and a year-by-year growth table.
Frequently Asked Questions
How does compounding frequency affect savings?
More frequent compounding leads to slightly higher returns because interest is earned on interest more often. The effect is noticeable over long periods, but daily versus monthly compounding adds only a few dollars a year on typical balances — rate and time horizon matter more.
What is a realistic interest rate?
High-yield savings accounts currently offer 4-5%, and long-term stock market averages run 7-10% before inflation. Use a rate appropriate for your actual savings vehicle. To project growth in purchasing power, subtract expected inflation — historically around 3% — for a real rate of return.
Should I include taxes?
Interest earned in standard savings accounts is taxable. For a conservative estimate, you can reduce your interest rate by your marginal tax rate.
Can I reach my goal faster by contributing more?
Yes, increasing contributions has a larger impact than small interest rate changes. Regular, consistent deposits are the most reliable way to grow savings.
What is the difference between APY and APR?
APY (annual percentage yield) includes the effect of compounding and shows what you actually earn in a year, while APR (annual percentage rate) is the nominal rate before compounding. A 4.50% nominal rate compounded monthly equals about 4.594% APY. Always compare savings accounts by APY.
How much should I keep in my emergency fund?
Most experts recommend three to six months of essential expenses. For $4,000 in monthly essentials, that is $12,000 to $24,000. Aim higher if your income is variable or your household relies on a single earner.
Are high-yield savings accounts safe?
Yes, provided the institution is federally insured. FDIC insurance covers bank deposits up to $250,000 per depositor, per institution; NCUA provides the same protection at credit unions. Your principal cannot lose value — only the variable rate changes.