APY vs. APR: Compare Savings Rates on the Same Basis

APY and APR both express an annual rate, but they do not always describe the same thing. For a deposit, annual percentage yield (APY) includes the effect of compounding over one year. A nominal annual percentage rate (APR) can leave that effect outside the headline number. Comparing a 5.00% APR with a 5.00% APY as if they were identical can therefore produce the wrong ranking.

The practical task is simple: put every offer on an effective annual basis, then check the conditions that determine whether you can actually earn that rate. This guide uses a hypothetical $10,000 deposit and the Calquio APY Calculator to show each step.

Convert a nominal rate to an effective annual yield

For a nominal annual rate r compounded n times per year, the effective annual yield is:

APY = (1 + r / n)^n - 1

The Consumer Financial Protection Bureau's Regulation DD appendix specifies how APY is calculated for U.S. deposit disclosures. The important idea for a comparison is that APY reflects the relationship between principal and interest over a 365-day period. A quoted nominal rate does not become APY until the compounding schedule is included.

Enter these inputs in the calculator:

The calculator returns an APY of 5.1162%. The independent calculation is:

(1 + 0.05 / 12)^12 - 1 = 0.0511619...

Rounded to four decimal places as a percentage, that is 5.1162%. The result is not 5% multiplied by 12; 5% is already the annual nominal rate. Monthly compounding divides it into twelve periodic rates and compounds those periods.

Translate the rate difference into money

On the hypothetical $10,000 balance, assuming the balance remains unchanged, the rate is available for the full year, and no fees or withdrawals apply:

$10,000 × 0.0511619 = $511.62

At a simple 5.00% annual return, the interest would be $500.00. Compounding adds about $11.62 in this one-year illustration. That amount is modest because the time horizon is short and the rate difference is only 0.1162 percentage point.

This example is a check on the conversion, not a promise of earnings. A variable-rate account can change during the year. Some accounts require a minimum balance, qualifying deposits, a limited balance tier, or other actions. A monthly maintenance fee can matter more than the APR-to-APY difference.

The FDIC's Money Smart material on savings accounts explains that APY includes compounding and recommends comparing APYs and account disclosures. It also notes that fees and minimum-balance requirements belong in the decision. Those conditions cannot be recovered from the headline yield alone.

Compare offers without mixing labels

Use this sequence for each account:

1. Record whether the published number is APY, APR, or an interest rate.
2. If it is a nominal annual rate, record the compounding frequency and convert it to APY.
3. Confirm the balance range to which the advertised yield applies.
4. Subtract unavoidable annual fees from the expected interest in dollars.
5. Check whether the rate is fixed or variable and whether it is promotional.
6. Compare access limits, withdrawal rules, deposit insurance eligibility, and other account terms separately.

Suppose Account A advertises 5.00% APR compounded monthly and Account B advertises 5.08% APY. The conversion shows that Account A's effective yield is 5.1162%, so it ranks higher on yield alone. That conclusion can reverse if Account A charges an unavoidable $5 monthly fee: $60 of fees would exceed the roughly $3.62 gross-interest advantage on $10,000 over Account B ($10,000 × (5.1162% - 5.08%)).

This is why the comparison should end in dollars, not with whichever percentage looks larger.

Test the effect of compounding frequency

Holding the hypothetical 5.00% nominal annual rate constant gives:

The calculation shows diminishing differences as compounding becomes more frequent. Moving from annual to monthly compounding changes APY by about 0.1162 percentage point; moving from monthly to daily changes it by only about 0.0105 percentage point.

Do not use this table to assume that a bank offering daily compounding must have the better account. Providers can set different nominal rates, fees, tiers, and conditions. Recalculate with the actual inputs from each disclosure.

You can also run the conversion in reverse as a disclosure check. Enter 5.1162% APY with monthly compounding and the calculator returns approximately 5.00% nominal APR. A small difference in the final digits can come from the published APY having already been rounded. Preserve the unrounded calculator result when comparing dollar outcomes, and round only the final currency amount. Otherwise, repeated rounding can create a few cents of unexplained difference.

Know what the calculator does not decide

The calculator converts rates; it does not verify an institution, forecast a variable rate, model taxes, apply account fees, or determine deposit-insurance coverage. APR also has specialized legal meanings in credit disclosures, where fees and calculation rules can differ from a simple nominal-rate conversion. Do not use this deposit-rate example to estimate the full cost of a loan.

This article is an illustrative calculation, not personalized financial, tax, or investment advice. Read the current account agreement and official disclosure, and consider professional advice when the product or tax treatment is material to your decision.

Sources

• CFPB, Regulation DD, Appendix A: Annual Percentage Yield Calculations — current U.S. deposit-disclosure calculation rules; accessed July 29, 2026.
• FDIC Money Smart: Savings Accounts — consumer guidance on compounding, APY, fees, and account comparisons; accessed July 29, 2026.