APY to APR Calculator – Convert Annual Percentage Yield & Rate
The APY to APR calculator converts between Annual Percentage Yield (APY) and Annual Percentage Rate (APR) based on compounding frequency. APY shows the actual annual return including compound interest effects, while APR represents the simple annual rate without compounding. Use this bidirectional calculator to compare savings accounts (typically quoted in APY) with loans or credit cards (quoted in APR), or to understand how compounding frequency—daily, monthly, quarterly, or annually—affects your true earnings or borrowing costs.
📈 APR to APY Converter
Convert Annual Percentage Rate to Yield
APY Conversion Results
Interest Comparison on $10,000
| Metric | Value |
| APR (Simple) | 5.00% |
| APY (Compound) | 5.12% |
| Compounding Periods/Year | 12 |
| Interest with APR (simple) | $500 |
| Interest with APY (compound) | $512 |
| Extra Earnings from Compounding | $12 |
📉 APY to APR Converter
Convert Annual Percentage Yield to Rate
APR Conversion Results
Interest Breakdown on $10,000
| Metric | Value |
| APY (Compound) | 5.12% |
| APR (Simple) | 5.00% |
| Compounding Periods/Year | 12 |
| Actual Annual Earnings (APY) | $512 |
| Nominal Rate Needed (APR) | 5.00% |
Understanding APR vs APY
Annual Percentage Rate (APR) and Annual Percentage Yield (APY) are two different ways of expressing interest rates, and understanding the distinction is crucial for making informed financial decisions about savings, investments, and loans.
What is APR (Annual Percentage Rate)?
APR is the simple annual interest rate without accounting for compounding within the year. It's the nominal rate that's applied to your principal. APR is commonly used for:
- Credit cards: Shows the yearly cost of borrowing
- Personal loans: Indicates the annual interest charge
- Mortgages: Displays the base interest rate
- Auto loans: Shows simple annual rate
What is APY (Annual Percentage Yield)?
APY accounts for compound interest—the interest earned on both your principal and previously earned interest. APY always equals or exceeds APR because it includes compounding effects. APY is commonly used for:
- Savings accounts: Shows actual annual return
- CDs (Certificates of Deposit): Displays true yield
- Money market accounts: Indicates real earnings
- High-yield savings: Shows compound growth
Key Difference: APR tells you the rate, APY tells you the yield. For savings, higher APY is better (you earn more). For loans, lower APR is better (you pay less). The more frequently interest compounds, the bigger the gap between APR and APY.
APR to APY Conversion Formula
Converting APR to APY requires accounting for the compounding frequency:
APR to APY Formula:
Where:
- APY = Annual Percentage Yield (as decimal)
- APR = Annual Percentage Rate (as decimal)
- n = Number of compounding periods per year
Example APR to APY Conversion:
Given: 5% APR with monthly compounding (n = 12)
Step 1: Convert APR to decimal = 5% = 0.05
Step 2: Divide by compounding periods = 0.05 / 12 = 0.004167
Step 3: Add 1 = 1 + 0.004167 = 1.004167
Step 4: Raise to power of n = (1.004167)^12 = 1.05116
Step 5: Subtract 1 = 1.05116 - 1 = 0.05116
Result: APY = 5.12% (compared to 5% APR)
Impact: On $10,000, you earn $512 instead of $500—an extra $12 from compounding
APY to APR Conversion Formula
Converting APY back to APR (nominal rate) requires the inverse calculation:
APY to APR Formula:
Where:
- APR = Annual Percentage Rate (as decimal)
- APY = Annual Percentage Yield (as decimal)
- n = Number of compounding periods per year
Example APY to APR Conversion:
Given: 5.12% APY with monthly compounding (n = 12)
Step 1: Convert APY to decimal = 5.12% = 0.0512
Step 2: Add 1 = 1 + 0.0512 = 1.0512
Step 3: Take nth root = (1.0512)^(1/12) = 1.004167
Step 4: Subtract 1 = 1.004167 - 1 = 0.004167
Step 5: Multiply by n = 0.004167 × 12 = 0.05
Result: APR = 5.00% (the nominal rate needed to achieve 5.12% APY)
Impact of Compounding Frequency
Compounding frequency dramatically affects the difference between APR and APY:
| Compounding | Periods/Year (n) | 5% APR → APY | 10% APR → APY | Difference |
|---|---|---|---|---|
| Annually | 1 | 5.00% | 10.00% | 0.00% |
| Semi-Annually | 2 | 5.06% | 10.25% | +0.06% / +0.25% |
| Quarterly | 4 | 5.09% | 10.38% | +0.09% / +0.38% |
| Monthly | 12 | 5.12% | 10.47% | +0.12% / +0.47% |
| Daily | 365 | 5.13% | 10.52% | +0.13% / +0.52% |
Key Insight: The higher the APR, the more significant the compounding effect. At 10% APR with daily compounding, you earn 10.52% APY—an extra 0.52% annually. On $100,000, that's an additional $520 per year just from more frequent compounding. Always compare APY to APY and APR to APR—never mix them.
Real-World APY and APR Examples
Savings Account Comparison
Two banks advertise "5%" rates but use different compounding:
- Bank A: 5% APR, annual compounding = 5.00% APY → Earns $500 on $10,000
- Bank B: 5% APR, daily compounding = 5.13% APY → Earns $513 on $10,000
- Result: Bank B pays $13 more per year despite same stated "5%" rate
Credit Card APR
Credit card with 18% APR, compounded daily:
- Stated APR: 18.00%
- Actual APY: 19.72% (due to daily compounding)
- On $10,000 balance: You pay $1,972 in interest, not $1,800
- Impact: $172 more in interest than simple calculation suggests
When to Use APR vs APY
Use APR When:
- Comparing loans: Credit cards, mortgages, auto loans typically quoted in APR
- Simple interest: Some loans compound annually or use simple interest
- Regulatory requirements: Truth in Lending Act requires APR disclosure
- Nominal rate needed: You want the base rate without compounding
Use APY When:
- Comparing savings: High-yield savings, CDs, money market accounts
- True earnings: You want to know actual annual return
- Investment accounts: Shows compound growth effect
- Frequent compounding: Daily or monthly compounding makes APY more accurate
⚠️ Common Mistake: Never compare APR from one account to APY from another—you're comparing apples to oranges. A savings account advertising "5% APY" is better than one advertising "5% APR" even though the numbers look the same. Always convert to the same metric (preferably APY for savings, APR for loans) before comparing.
Frequently Asked Questions
Practical Tips for Using APR and APY
For Savers and Investors
- Always compare APY: Ignore stated APR, only compare APY between savings accounts
- Seek daily compounding: Maximizes earnings, especially on high-yield savings
- Calculate true return: Use APY calculator to find real annual earnings
- Watch for tricks: Some banks advertise APR to look better—convert to APY
- Compound frequency matters: 5% APR daily beats 5.1% APR annually
For Borrowers
- Compare APR on loans: Lower APR = less interest paid (if same compounding)
- Check compounding: Daily compounding on credit cards makes APR worse
- Calculate APY on debt: See true annual cost including compound effect
- Pay more frequently: Biweekly payments reduce compound interest impact
- Understand credit cards: 18% APR ≈ 19.7% APY with daily compounding