Loan Calculator
Calculate your loan payments, total interest, and see the full amortization schedule for any personal loan.
Enter Your Information
Results
About the Loan Calculator
Personal loans, auto loans, student loans, business loans — almost all installment loans use the same amortization formula. This calculator and page show you how the monthly payment is built, why interest dominates the early payments, and how to compare loan offers that have different terms.
The Formula
Monthly payment M = P × r × (1+r)^n ÷ ((1+r)^n − 1), where P is principal, r is the monthly interest rate (APR ÷ 12, as decimal), n is total months. Total interest = (M × n) − P.
Worked Example
$15,000 personal loan at 9.99% APR for 5 years (60 months). r = 0.0999 ÷ 12 = 0.00833. M = 15000 × 0.00833 × (1.00833)^60 ÷ ((1.00833)^60 − 1) ≈ $318/month. Total paid = $318 × 60 = $19,080. Interest = $4,080.
APR vs interest rate vs APY
Interest rate is the cost of borrowing the principal. APR (Annual Percentage Rate) includes most fees (origination, processing) and is the legal disclosure rate — use APR to compare loans. APY (Annual Percentage Yield) is for savings, not loans. Two loans with the same interest rate but different fees can have noticeably different APRs.
Loan term: shorter saves money but raises the monthly payment
A $20,000 loan at 8% for 3 years = $627/month, $2,572 total interest. Same loan over 5 years = $406/month, $4,332 interest. Same over 7 years = $312/month, $6,200 interest. The longer you stretch the loan, the more affordable the monthly payment but the more total interest you pay. Borrow on the shortest term you can comfortably afford.
Secured vs unsecured loans
Secured loans (auto, mortgage, secured personal) use an asset as collateral and have lower rates. Unsecured personal loans rely only on your credit and income — rates run 6-36% depending on credit score. If you have an asset to pledge, you'll get a meaningfully better rate.
Common Mistakes
- Comparing loans by monthly payment instead of APR and total interest.
- Picking the longest available term to lower the monthly payment without seeing the total cost.
- Ignoring origination fees. A 5% origination fee on a $20,000 loan is $1,000 of cost not shown in the rate.
- Borrowing against a vehicle for non-vehicle purposes. If you can't pay, you lose transportation too.
Frequently Asked Questions
Can I pay off a loan early?
Almost always yes. A few legacy loans have prepayment penalties — check the agreement. Personal loans, mortgages (post-2014), and most auto loans have no penalty.
What credit score do I need for the best rate?
740+ for the lowest advertised rates. Below 680, expect rates several percentage points higher.
This calculator is for informational purposes only and does not constitute financial, tax, or legal advice. Consult a licensed professional before making significant financial decisions.