Loan calculator guide
This loan calculator estimates the payment and total cost for a fixed-rate installment loan. It works for personal loans, auto loans, student loan planning, equipment financing, or any debt with a fixed interest rate and fixed payoff term.
How to use it
- Enter the amount borrowed, annual interest rate, and loan term.
- Add an extra monthly payment to see how faster payoff changes the result.
- Compare total interest, not only the monthly payment.
Calculation method
The formula is the same amortization structure used by many fixed loans. If the rate is 0%, the calculator divides the principal evenly across the term.
Example scenario
A $25,000 loan at 8.5% for 5 years has a payment near $513 per month and total interest near $5,800. Paying extra each month lowers the balance faster and reduces interest.
Quality check
If your lender charges origination fees, variable rates, balloon payments, or prepayment penalties, this calculator will not capture those details. It is best used for clean comparisons between loan amount, rate, term, and extra payment.
How to use this calculator
- Enter realistic values that match your current situation.
- Press Calculate to refresh the estimate.
- Compare the main result with the supporting details in the result panel.
- Change one input at a time to see which variable affects the result most.
FAQ
Why does a lower payment sometimes cost more?
A longer term lowers the monthly payment but usually increases total interest.
Is extra payment applied to principal?
This calculator assumes extra payment reduces principal immediately.
Can this replace a lender quote?
No. Use it as a planning estimate before checking final contract terms.