APY Calculator
Convert a nominal interest rate into annual percentage yield and back.
What the APY Calculator does
APY is what you actually earn in a year once compounding is counted; the nominal rate is what gets advertised. Comparing two savings accounts is only fair on an APY basis, because compounding schedules differ.
Formula
APY = (1 + r/n)ⁿ − 1Continuous: APY = eʳ − 1Nominal = n × ((1 + APY)^(1/n) − 1)
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Convert | one of 2 options | Yes | — |
| Rate | % | Yes | — |
| Compounding frequency | one of 8 options | Yes | — |
| Balance | selected currency | Optional | Optional — shows the interest in currency terms. Accepts 0 or more. |
| Currency | one of 10 options | Optional | — |
How to use it
- Choose Convert and Compounding frequency.
- Enter Rate.
- Optionally add Balance.
- Select Calculate.
Worked example
A savings account quotes 4.5% compounded daily.
- Mode
- Nominal → APY
- Rate
- 4.5
- Frequency
- Daily
APY = 4.6028%, about 0.10 percentage points above the nominal rate.
Frequently asked questions
What is the difference between APR and APY?
APR is the nominal rate plus fees and ignores compounding; APY includes compounding. Lenders quote APR, savings accounts quote APY — each shows their product in the better light.