Interest Rate Calculator
APY Calculator
Convert a nominal annual interest rate and compounding frequency into annual percentage yield and estimated one-year interest.
Use the APY Calculator
Your results
- Annual percentage yield
- 0.00%
- Balance after one year
- $0.00
- Interest earned in one year
- $0.00
How this calculator works
- What it does
- Convert a nominal annual interest rate and compounding frequency into annual percentage yield and estimated one-year interest.
- Inputs used
- The estimate uses nominal annual rate (%), compounding frequency, and starting balance.
- Calculation approach
- The calculator applies the relationships defined for the apy calculator to those inputs and updates annual percentage yield, balance after one year, and interest earned in one year.
- How to read the result
- Treat the result as a scenario based on the values entered. Compare a few reasonable inputs and consider costs, taxes, timing, or risks that the calculator does not include.
How to Use This Calculator
- Enter Nominal annual rate (%) using values that match the scenario you want to evaluate.
- Enter Compounding frequency using values that match the scenario you want to evaluate.
- Enter Starting balance using values that match the scenario you want to evaluate.
- Review the assumptions for the apy calculator, especially rates, time periods, and optional amounts.
- Select Calculate to update the results, then adjust one input at a time to compare scenarios.
Understanding the Results
- Annual percentage yield
- A percentage or comparison measure that summarizes the relationship between the calculator's key values.
- Balance after one year
- The balance after one year estimated by the APY Calculator using nominal annual rate (%), compounding frequency, and starting balance and the other values entered.
- Interest earned in one year
- The portion of the result attributed to growth rather than money contributed or originally invested.
Common Mistakes
- Treating an assumed return, growth rate, inflation rate, or yield as guaranteed.
- Leaving out taxes, fees, inflation, or timing differences that can affect real-world results.
- Mixing monthly and annual figures or entering percentages in the wrong units.
- Relying on one projection instead of comparing a range of reasonable assumptions.
Frequently asked questions
What is APY?
Annual percentage yield is the effective one-year rate after accounting for compounding within the year.
How is APY different from APR?
APY includes the effect of compounding. A nominal APR or stated annual rate generally does not fully express that within-year compounding effect.
Why is APY higher with more frequent compounding?
Interest is added to the balance sooner, so earlier interest can earn additional interest during later periods.
Is APY the same as an investment return?
No. APY commonly describes deposit interest under stated terms. Market investment returns vary and can include losses.
Does APY include account fees or taxes?
Not in this calculator. Fees, taxes, balance tiers, changing rates, and withdrawal restrictions can change the amount retained.
What does the APY Calculator calculate?
Convert a nominal annual interest rate and compounding frequency into annual percentage yield and estimated one-year interest. The result is based only on the inputs and assumptions shown on the page.
How should I interpret the annual percentage yield from the APY Calculator?
Use it as an estimate for the scenario entered, not as a guarantee or personal recommendation. Test changes to nominal annual rate (%), compounding frequency, and starting balance to see which assumptions have the greatest effect.