Interest Rate Calculator
Find APR from payment and term, convert between APR and APY, calculate effective rate with fees, or compare loan rates. Get instant results.
Your Details
Choose a calculation type, enter your numbers, and click Calculate to see your interest rate, APR/APY conversion, effective rate with fees, or rate comparison.
Interest Rate (APR)
0%
Monthly Rate
0%
Total Payments
$0
Total Interest
$0
Loan Term
0 months
Principal vs Interest
0%
APR
0%
APY
0%
Difference
0%
Formula
APR vs APY
Effective Annual Rate
0%
Nominal Rate
0%
Monthly Payment
$0
Total Fees
$0
Net Proceeds
$0
Total Cost
$0
Cost Breakdown
Rate Comparison
| Rate | Monthly Payment | Total Interest | Total Cost |
|---|
Savings (lowest vs highest rate)
Monthly: $0
Total interest: $0
Monthly Payment by Rate
Complete User Guide
What is APR vs APY?
APR (Annual Percentage Rate) is the nominal rate before compounding. APY (Annual Percentage Yield) is the actual return after compounding. When interest compounds more than once per year, APY is higher than APR. This calculator finds APR from payment and term, converts between APR and APY, and shows effective rate when fees are included.
Calculation Types
- Find Rate: Enter loan amount, monthly payment, and term to get the implied APR.
- APR → APY: Convert a stated APR to APY for a given compounding frequency.
- APY → APR: Convert APY back to the equivalent APR.
- Effective Rate: Include origination fees, points, and other fees to see the true cost of the loan (effective annual rate).
- Compare Rates: Enter multiple rates to compare monthly payments and total interest.
Formulas Used
APY = (1 + APR/n)^n − 1
APR = n × [(1 + APY)^(1/n) − 1]
n = compounding periods per year. Find rate uses the loan payment formula solved for rate (Newton-Raphson).
Important Notes
- This tool is for education and estimation only. Not financial or legal advice.
- Effective rate with fees reflects the true cost when you receive less than the full loan amount.