Calculate APY, interest earned, and effective returns easily. Model cases across days, rates, and periods. See clear results above the form for faster comparisons.
| Deposit | Rate | Compounding | Days | Basis | Effective APY | Gross Ending Balance |
|---|---|---|---|---|---|---|
| $10,000.00 | 4.25% | Monthly | 365 | 365 | 4.3338% | $10,433.38 |
| $25,000.00 | 5.10% | Daily | 180 | 365 | 5.2319% | $25,636.70 |
| $5,000.00 | 3.75% | Quarterly | 90 | 360 | 3.8031% | $5,046.88 |
These figures are sample outputs for illustration.
1. Effective APY
APY = (1 + r / n)n - 1
2. Time in Years
Years = Days / Day Basis
3. Gross Ending Balance
Ending Balance = P × (1 + r / n)n × Years
4. Gross Interest
Gross Interest = Ending Balance - P
5. Net Interest
Net Interest = Gross Interest - Tax Amount - Account Fee
6. Annualized Yield
Annualized Yield = (Ending Balance / P)365 / Days - 1
Where: P is deposit amount, r is annual rate as a decimal, and n is compounds per year.
Money market annual percentage yield helps you compare cash returns fairly. A quoted rate alone can mislead. Compounding changes the true outcome. This calculator turns those moving parts into one clear figure.
Annual percentage yield, or APY, shows the effective yearly return after compounding. Money market accounts may compound daily, monthly, or on another schedule. Two accounts can share the same stated rate but produce different earnings. APY exposes that difference quickly.
A solid APY review starts with deposit size, quoted annual rate, and compounding frequency. Term length also matters. A 90 day holding period does not tell the full yearly story by itself. Annualizing the result makes comparison easier. The calculator also estimates gross balance, interest earned, tax drag, fee impact, and real yield after inflation.
Money market savers often use APY when choosing between savings accounts, sweep products, and short term cash tools. It supports better planning. You can test conservative and aggressive scenarios. You can also see how a small rate change affects ending value. That helps with treasury decisions, emergency funds, and idle cash management.
Use the calculator when rates change or when banks advertise promotional returns. Enter the deposit amount first. Add the nominal rate next. Choose the compounding schedule that matches the product terms. Then enter the investment days and optional adjustments such as taxes, inflation, and fees. The result appears above the form for quick review.
The most useful metric is usually effective APY. It captures compounding over a full year. Gross ending balance shows dollar growth. Net balance shows what remains after costs. Real APY adjusts for inflation and gives a better purchasing power view. Monthly and daily equivalent rates help with detailed planning.
Because money market yields are sensitive to compounding assumptions, even small input changes matter. Switching from monthly to daily compounding can lift effective return. Extending the holding period can also change annualized output. Reviewing several scenarios is the safest way to judge a product fairly.
A careful APY comparison reduces guesswork. It also prevents overestimating returns from simple interest quotes. Use this page to compare scenarios side by side, export the results, and make more informed cash decisions.
APY is the effective annual return after compounding. It gives a fuller picture than a simple quoted rate. That makes account comparisons more reliable.
More frequent compounding usually increases the final yield. Daily compounding can produce a slightly higher return than monthly compounding at the same stated rate.
APR is the stated annual rate without showing compounding impact. APY includes compounding and reflects the effective yearly return.
Annualized yield depends on the actual holding period result. Effective APY comes from the compounding formula over a full year. Fees and taxes can widen the gap.
Yes, when you want a realistic estimate. Taxes reduce earned interest. Fees lower net return. Including both improves planning accuracy.
Real APY adjusts the estimated return for inflation. It helps show whether your cash growth is actually improving purchasing power.
Use 360 when the product terms or institution calculations follow a 360 day convention. Use 365 when the account terms specify actual daily annualization.
Yes. Enter each scenario separately and compare APY, net ending balance, and real yield. That makes side by side decisions easier.