MONEY / BANKING & SAVING

APR vs. APY: How to Compare Saving and Borrowing Rates

Learn what APR and APY measure, how compounding changes APY, and what to check beyond the headline rate when comparing savings accounts or loans.

zcompound editorial team10 min read8 linked sources

In this guide

APR and APY both turn a rate into an annual percentage, but they answer different questions.

APR (annual percentage rate) is mainly a borrowing measure. It expresses the cost of credit as a yearly rate. Which charges it includes depends on the product and the disclosure rules.
APY (annual percentage yield) is mainly a deposit measure. It expresses the interest a deposit can earn over a year with compounding included.

The quick rule is simple: when comparing similar savings products, a higher APY usually means more interest under the stated assumptions. When comparing similar loans, a lower APR usually means a lower annualized borrowing cost. But neither number tells the whole story.

Jurisdiction note: This guide uses U.S. Consumer Financial Protection Bureau (CFPB) definitions because they provide precise, standardized examples. Legal definitions, required disclosures, terminology, and consumer protections differ by country. Always read the documents for the product and jurisdiction you are actually considering.

What APR measures when you borrow

Under the CFPB’s U.S. rules for closed-end credit, APR is a measure of the cost of credit expressed as a yearly rate. The calculation links the amount and timing of value received by the borrower with the amount and timing of payments. That makes APR more useful than a quoted interest rate alone when comparing like loans. [1]

APR is not identical across every borrowing product:

For an auto loan, the CFPB explains that APR can include the interest rate plus certain additional lender charges, such as origination fees. [2]
For a credit card, the interest rate is typically stated as an APR. A card issuer may derive a daily periodic rate by dividing the APR by 360 or 365, depending on the agreement. [3]
Annual fees, late fees, balance-transfer fees, optional add-ons, and other charges may not all be captured by the rate you focus on. The product’s fee schedule and agreement still matter.

So “12% APR” does not mean “this debt will cost exactly 12% of the original amount.” The dollar cost also depends on the balance, term, payment timing, rate changes, fees, and whether interest is charged on previously accrued interest.

What APY measures when you save

Under U.S. Regulation DD, APY is the annual percentage that reflects the total interest paid on a deposit account based on both the interest rate and the frequency of compounding over a 365-day period. The related “interest rate” does not reflect compounding. [4]

Compounding happens when credited interest becomes part of the balance that can earn later interest. If two deposit accounts have the same nominal interest rate but compound at different frequencies, the account that compounds more frequently can have the higher APY, provided the rate and all other assumptions are the same.

APY standardizes a useful part of the comparison, but it is not a promise that your actual balance will grow by exactly that percentage. Under the U.S. calculation rules for a typical account without a stated maturity, the illustration assumes the principal and interest remain on deposit for the year and that no deposits or withdrawals occur. Variable-rate, stepped-rate, and tiered accounts have additional rules. [5]

How compounding frequency changes APY

For a constant nominal annual interest rate, equal compounding periods, and no transactions, the simplified relationship is:

APY = (1 + r / n)^n − 1

where r is the nominal annual rate as a decimal and n is the number of compounding periods in a year.

When the nominal rate is positive, more frequent compounding gives interest more opportunities to earn interest. The effect is real, but the difference between monthly and daily compounding may be small. A tiny compounding advantage can also be outweighed by a monthly fee, a lower rate, or a balance rule.

Do not use this simplified formula for every product. An account with changing rates, balance tiers, a short term, mandatory interest payouts, or unusual day-count rules needs the method in its disclosure.

A simple APY example

Imagine a deposit with these assumptions:

starting balance: $1,000;
nominal annual interest rate: 5.00%;
rate stays fixed for one year;
no deposits, withdrawals, fees, or taxes;
all interest remains in the account.

Scroll sideways or use arrow keys to read the full table.

Compounding frequency	End-of-year balance	APY
Once a year	$1,050.00	5.00%
Monthly	$1,051.16	5.12%
Daily (365 times)	$1,051.27	5.13%

For monthly compounding, the calculation is (1 + 0.05 / 12)^12 − 1 = 0.05116, or about 5.12% APY. The CFPB’s Regulation DD appendix defines APY using the relationship between principal, interest earned, and the account term; this table applies that compounding logic to a deliberately simple illustration. [5]

These are demonstration values, not a current product offer or forecast. Rounding explains the displayed cents and percentages.

Why APR and APY are not a direct head-to-head comparison

APR and APY can look like opposites—one for money going out and one for money coming in—but they are not two labels for the same calculation.

Scroll sideways or use arrow keys to read the full table.

Question	Start with	Direction that is usually favorable	What to check next
What could a deposit earn with compounding under the stated assumptions?	APY	Higher	Rate changes, balance tiers, fees, access, term, deposit protection
What is the annualized cost of comparable borrowing?	APR	Lower	Amount financed, term, payment schedule, included and excluded fees, rate changes

Do not compare a savings account’s APY with a loan’s APR and interpret the gap as profit or loss. The cash flows, risks, fees, tax treatment, and legal calculation rules are different.

Even within borrowing, compare APR with APR, not APR with a lender’s simple interest rate. Within saving, compare APY with APY for the balance and term that apply to you.

How to compare savings rates

Start with the APY, then read the terms around it. U.S. deposit-account disclosures address the interest rate and APY, whether a variable rate may change, compounding and crediting frequency, minimum-balance rules, fees, transaction limits, and early-withdrawal penalties for time deposits. [6]

Use this sequence:

Match the account type and currency. A liquid savings account and a locked time deposit do different jobs. A foreign-currency account adds exchange-rate risk.
Use the APY for your balance tier. Some accounts pay different rates at different balances or apply a headline rate only after conditions are met.
Check whether the rate is fixed, variable, or promotional. A current APY on a variable-rate account does not guarantee the same rate for the next year.
Subtract likely fees in dollars. APY reflects interest, not the personal net result after every account fee. A maintenance fee can exceed a small interest advantage.
Check access and timing. Withdrawal limits, transfer delays, maturity dates, and early-withdrawal penalties matter, especially for an emergency fund.
Check protection and provider status. Deposit-protection systems, coverage limits, eligible account types, and institutions vary by country. Verify the provider and current local rules directly.

The best APY is not automatically the best place for every savings goal. The money’s job—daily spending, emergency access, or a known future date—sets the comparison.

How to compare borrowing rates

Start with APR only after making the offers comparable:

Use the same amount and purpose. A $5,000 installment loan and a revolving credit line do not create the same cash flows.
Match the repayment term and schedule. A lower APR over a much longer term can still produce a higher total dollar cost.
Separate the interest rate from APR. For products where APR includes specified finance charges, it can be higher than the interest rate.
List costs outside the headline APR. Review application, annual, late, transfer, prepayment, optional-service, and other relevant fees; inclusion varies by product and rule.
Check fixed, variable, and promotional periods. Ask when the rate can change and what replaces an introductory rate.
Read how interest is applied. Daily balances, grace periods, payment timing, and payment allocation can change what you actually pay.
Compare monthly payment and total payments as dollars. APR is a comparison tool, not a substitute for the full repayment schedule.

For most credit cards, the CFPB notes that purchase interest can be avoided by paying the balance in full each month by the due date, but the exact grace-period and balance rules come from the agreement. [3] For the wider context, see how interest rates affect borrowing, saving, and markets.

What neither headline rate tells you

Neither APR nor APY answers every practical question:

Affordability: APR does not decide whether a payment fits your cash flow.
Access: APY does not show how quickly you can reach the money or whether early withdrawal reduces earnings.
Rate changes: A displayed variable rate can move after you open the product.
Every fee and condition: Read the full disclosure and agreement.
Taxes: Interest received or paid can have different tax treatment by product and jurisdiction.
Purchasing power: APY is a nominal yield. If prices rise, each unit of money buys less; a broad price index is an average and may not match your own spending. [7]
Safety or suitability: A percentage does not verify the provider, deposit protection, currency risk, or fit with your goal.

A one-minute comparison checklist

Before choosing, write each offer in one row and fill in:

APR or APY, using the same measure across comparable products;
fixed, variable, stepped, or promotional rate;
compounding and crediting frequency for deposits;
amount, balance tier, and minimum-balance rule;
term, payment schedule, and total payment for borrowing;
maintenance, origination, annual, transfer, withdrawal, late, or early-exit fees that could apply;
access restrictions and processing time;
provider and deposit-protection status where relevant;
the date the quoted terms were checked.

If two offers still look close, compare the likely dollar result under the same realistic scenario. Keep the assumptions beside the answer.

Keep learning

APR and APY become easier to use once you can see how compounding works. Then connect the rate to the money’s job: accessible cash in Banking & Saving, borrowing choices in the Debt & Credit learning path, and the wider everyday-money map under Money.

This guide is general education, not individualized financial, legal, or tax advice. Actual costs, yields, protections, and rules depend on the product, provider, agreement, behavior, and jurisdiction.