Saving Account APY Calculator
Savings Account APY Calculator works out Annual percentage yield and Nominal annual rate from Nominal annual rate, Annual percentage yield (APY) and Interest is compounded. The default figures on this page give annual percentage yield of 4.602496 %; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
2 steps
- Rate per period = 4.5% / 365 = 0.01232877%
- APY = (1 + 0.0001232877)^365 - 1 = 4.602496%
Its 5 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
2 sources
Keep this result
Save it, change one figure, then compare the two
The calculation stays free. Save this scenario, adjust one assumption, save that too, and put them side by side to see exactly what the change costs you. A free account keeps 5 scenarios and 2 comparisons; Personal makes both unlimited and adds exports and private links. Nothing is saved unless you press Save.
What the Savings Account APY Calculator calculates
Converts between the annual percentage yield a bank advertises and the nominal rate behind it at any compounding frequency, derives the APY from interest actually credited using the Regulation DD formula, and grows a balance at a quoted yield.
How to use this Savings Account APY Calculator
Enter Nominal annual rate, Annual percentage yield (APY), Interest is compounded and Balance. Annual percentage yield updates as you type. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Annual percentage yield, Nominal annual rate and Rate per compounding period.
The method follows 12 CFR Part 1030 (Regulation DD), Appendix A - Annual Percentage Yield Calculation and Effective annual rate identity (1 + r/n)^n - 1, and its continuous limit e^r - 1.
What you can compare
Change one input at a time to see how it affects Annual percentage yield, Nominal annual rate and Rate per compounding period. The inputs you can vary are Nominal annual rate, Annual percentage yield (APY), Interest is compounded, Balance, Interest credited and Days the interest covers.
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
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Frequently asked questions
What is 5% APY on $1000?
Converts between the annual percentage yield a bank advertises and the nominal rate behind it at any compounding frequency, derives the APY from interest actually credited using the Regulation DD formula. On this page it is computed from Nominal annual rate, Annual percentage yield (APY) and Interest is compounded and shown as Annual percentage yield, Nominal annual rate and Rate per compounding period.
How much will $20,000 make in a high-yield savings account?
The calculation is free and does not require an account. An account is only needed for optional features such as saving, comparing, exporting, or sharing supported scenarios.
What's 4% APY on $10,000?
It needs Nominal annual rate, Annual percentage yield (APY), Interest is compounded, Balance, Interest credited and Days the interest covers. Nothing else is required, and the figures stay in your browser.
Is 4% APY monthly?
Converts between the annual percentage yield a bank advertises and the nominal rate behind it at any compounding frequency, derives the APY from interest actually credited using the Regulation DD formula. On the figures this page opens with — balance 1,000, interest credited 61.68 and days the interest covers 365 days — the annual percentage yield is 4.602496%. Put your own figures in their place and the working updates beside the result.
What information do I need for the Savings Account APY Calculator?
You need Nominal annual rate, Annual percentage yield (APY), Interest is compounded, Balance, Interest credited, Days the interest covers and How long the balance is held. The page opens with default figures that give annual percentage yield of 4.602496 %, so you can see the scale before entering your own.
What does this Savings Account APY Calculator show?
It shows Annual percentage yield, Nominal annual rate, Rate per compounding period, Balance at the end, Interest earned and Compounding periods a year, with the working and any warnings for your entries.