Loan Calculator
Any loan, any term
About This Calculator
A loan calculator determines the monthly payment, total interest paid, and total cost for any installment loan — car loans, personal loans, student loans, or any fixed-term debt. The payment formula is derived from the present value of an annuity, where the loan amount equals the discounted sum of all future payments.
Formula
M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1]
M = monthly payment, P = loan principal, r = monthly rate = annual rate/12, n = total months
Total interest = (M × n) − P
Example Calculation
$15,000 car loan at 6% annual interest for 48 months
- r = 0.06/12 = 0.005; n = 48
- M = 15000 × [0.005×(1.005)⁴⁸] / [(1.005)⁴⁸−1]
- M = 15000 × 0.005×1.2705 / 0.2705 = 15000×0.02349 = $352.28
Monthly payment: $352.28; Total interest paid: $1,909
Monthly Payment per $10,000 Borrowed
| Rate | 24 months | 36 months | 48 months | 60 months |
|---|---|---|---|---|
| 4% | $434 | $295 | $226 | $184 |
| 6% | $443 | $304 | $235 | $193 |
| 8% | $452 | $313 | $244 | $203 |
| 10% | $461 | $323 | $254 | $212 |
Frequently Asked Questions
What factors affect my monthly loan payment?
Three factors determine the payment: principal (larger loan = higher payment), interest rate (higher rate = higher payment), and loan term (longer term = lower monthly payment but more total interest paid).
Should I choose a shorter or longer loan term?
A shorter term means higher monthly payments but significantly less total interest. A longer term is easier on monthly cash flow but costs more overall. Choose the shortest term you can comfortably afford.
What is an amortization schedule?
An amortization schedule lists every payment, showing how much goes to interest versus principal. Early payments are mostly interest; later payments are mostly principal. Total payments remain constant throughout.
What is the difference between a fixed and variable rate loan?
A fixed-rate loan has the same interest rate for the entire term — predictable payments. A variable rate loan's rate adjusts periodically with market rates — it may start lower but can increase, making budgeting harder.