Convert any nominal rate to APY with daily, monthly, quarterly, or annual compounding.
This apy calculator is an apy savings calculator that shows how compound interest turns a simple interest rate into annual percentage yield. By entering your balance, nominal rate and compounding schedule, the apy calculator estimates your effective APY, interest earned and final savings or CD balance so you do not have to guess how to calculate apy by hand.
The apy calculator compares the stated interest rate with the effective APY once compounding is applied. This makes the apy savings calculator useful when you want to see how much more you earn with monthly or daily compounding instead of simple interest.
As an apy calculator savings tool, this page lets you test annual, quarterly, monthly, weekly and daily compounding. The formula the apy calculator uses matches typical bank disclosures for annual percentage yield.
You can use this apy calculator as a quick cd calculator apy helper by entering a CD rate and matching compounding schedule, or as an apy calculator savings tool for regular high‑yield savings accounts.
This apy calculator converts a nominal interest rate into annual percentage yield based on your chosen compounding frequency. It then applies that APY to your balance and time horizon so you can see total interest and final savings, similar to other apy savings calculator and cd calculator apy tools.
To calculate APY from an interest rate, you take the rate in decimal form, divide by the number of compounding periods per year, add 1, raise to the power of the number of periods, and subtract 1. The formula this apy calculator uses is APY = (1 + r / n)^n − 1, where r is the nominal rate and n is the compounding frequency.
Yes. While it is built as an apy calculator savings tool, you can treat it like a cd calculator apy helper by entering the CD rate, compounding schedule and term. The apy calculator will then show effective APY and total interest over the CD term.
Simple interest ignores compounding and only multiplies balance by the nominal rate and time. The apy calculator, by contrast, includes the effect of compounding, so APY is usually higher than the simple interest rate for the same account.
This independent apy calculator is similar to many bank apy savings calculator pages, but it is not tied to any specific product. You can plug in rates from different banks, compare APY results and pick the savings or CD account that best fits your goals.
Type the stated interest rate (APR) as a percentage. This is the rate the bank quotes before compounding.
Choose daily, monthly, quarterly, or annual compounding. Most savings accounts compound daily; bonds usually compound semi-annually.
APY = (1 + r/n)^n - 1, where r is the nominal rate and n is the compounding periods per year. We show both the APY and the effective annual interest.
For related calculations, try our compound interest calculator.
Effective annual yield for a savings account or CD at common advertised APYs (assuming daily compounding):
| Advertised APY | Daily compounding | Monthly compounding | Effective yield |
|---|---|---|---|
| 3.50% | 3.56% | 3.54% | ~3.55% |
| 4.00% | 4.07% | 4.05% | ~4.06% |
| 4.50% | 4.58% | 4.56% | ~4.57% |
| 5.00% | 5.09% | 5.06% | ~5.08% |
Effective yield = (1 + APY/n)^n - 1, where n = compounding periods per year. Daily compounding slightly outperforms monthly at same APY. Use the calculator above with custom compounding.
Cross-checked against authoritative formulas (IRS, NIST, ACSM) and updated for 2025/2026 tax years and rates.
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An APY calculator is a free financial tool that converts a nominal interest rate into the annual percentage yield (APY), accounting for compounding frequency. Our APY calculator works for savings accounts, CDs, money market accounts, and any interest-bearing product. The APY calculator shows how monthly vs daily compounding changes the real return.
How it works
Our apy calculator lets you convert a nominal interest rate to APY with any compounding frequency.
Type the annual interest rate (APR) as a percentage. The APY calculator accepts any rate from 0% to 50%. This is the rate the bank advertises, before compounding.
Choose how often interest compounds: annually, semi-annually, quarterly, monthly, or daily. Most savings accounts compound daily; CDs compound monthly or daily. The APY calculator applies the compounding formula for the chosen frequency.
The result shows the APY (Annual Percentage Yield), which is what you actually earn in a year. The APY calculator also shows the effective annual rate for comparison. The share button creates a link with your inputs pre-filled.
Learn what APR is, how it differs from APY, and why these rates matter for loans, savings, and credit cards.
Learn how compound interest works and how APY reflects the true earning potential with compounding.