Savings Interest Calculator
Enter your deposit, rate, and time to see exactly what your savings will earn on this calculator, with compounding included.
How much you're starting with.
Optional. Set to 0 if you won't add more.
| Year | Contributions | Interest earned | Ending balance |
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This is a general estimate, not financial, investment, or tax advice.
Table of contents
How to Use This Calculator
Enter your starting deposit, then your monthly contribution if you're adding money regularly (0 if not). Enter your account's APY and how often it compounds -- most online banks compound daily or monthly, check your account terms if you're not sure. Set how many years you're planning to save. The result panel updates live as you type, showing your ending balance, total interest earned, and a year-by-year breakdown below it.
How compound interest works
Compound interest means the interest your money earns gets added back to your balance, so future interest is calculated on a bigger number. This calculator uses the standard compound interest formula with regular contributions:
A = P(1 + r/n)nt + PMT × ((1 + r/n)nt − 1) / (r/n)
Where A is your ending balance, P is your starting deposit, r is your APY as a decimal, n is compounding periods per year, t is years, and PMT is your periodic contribution. Your starting deposit grows on its own, while each new contribution starts earning interest from the moment it's added. See Compound Interest Formula Explained for every variant of this formula, with worked examples.
How compounding frequency changes the result
More frequent compounding (daily versus monthly, for example) means interest gets added back to your balance more often, which produces a slightly larger total. For most account sizes and time frames the difference between daily and monthly compounding is small in dollar terms. See how compounding frequency affects your savings for a full breakdown with worked examples.
What counts as a good APY right now
National average savings account APYs have historically sat well under 1%, while high-yield savings accounts have commonly offered APYs in the 3% to 5% range in recent periods. This moves with the Federal Reserve's benchmark rate, so treat any single number as a snapshot rather than a fixed figure -- check your bank's current rate before relying on it. See what APY means for more on how to compare accounts.
Sources
- National average and high-yield rate ranges — Axos Bank, citing FDIC data
- Compound interest formula with regular contributions — Bankrate
Frequently asked questions
How is compound interest calculated on a savings account?
Your bank applies your APY to your current balance at each compounding period, then adds that interest back to the balance so it starts earning its own interest. This calculator does the same math using the deposit, contribution, rate, and compounding frequency you enter.
What's the difference between interest rate and APY?
APY already includes the effect of compounding, while a stated interest rate alone does not. Two accounts with the same nominal rate but different compounding frequencies will have slightly different APYs. See What Is APY for the full explanation.
Does compounding frequency really make a big difference?
It can matter more over longer time frames or larger balances, but the gap between common frequencies like monthly and daily is usually small. See How Compounding Frequency Works for worked examples.
Is this calculator accurate for my actual bank account?
It models the standard compound interest formula. Actual results depend on your bank's specific compounding schedule, any fees, and rate changes over time, since APY on variable-rate accounts can change.
What counts as a good APY right now?
This depends on current market conditions. Enter your own bank's advertised APY above rather than relying on a number baked into this page, since rates change with the Federal Reserve's benchmark rate.
How This Calculator Is Verified
Built by Cedrick Reese. Every formula on this page is checked against multiple independent sources before publishing, and cross-verified against real calculations before this page went live -- not just written once and trusted.
Last reviewed: August 26, 2026