What does this loan calculator do?
This calculator models a fixed-rate installment loan repaid monthly. It shows the required scheduled payment, total interest, total cash payments, planned payoff date and the balance after every payment.
For a home loan with tax, insurance, mortgage insurance and HOA inputs, use the Mortgage Calculator. For vehicle price, trade-in, rebate, sales tax and dealer-fee planning, use the Auto Loan Calculator.
Loan payment and amortization formula
P is the financed balance, r is the monthly rate, and n is the number of monthly payments. A 0% loan divides principal evenly by the number of payments.
For each period, interest equals the opening balance multiplied by the monthly rate. Scheduled principal and any extra principal reduce the balance. Because currency is displayed to cents while calculations retain precision, a lender schedule can differ slightly due to rounding conventions.
How the fee options work
- Added to balance: the fee increases the financed principal while the requested loan amount remains the assumed cash received.
- Deducted from proceeds: the payment uses the requested balance, but net cash received is reduced by the fee.
- Paid upfront: the requested balance is financed and the fee is treated as a separate initial cash outflow.
The fee-adjusted effective annual cost estimate solves for the rate that equates net initial proceeds with the entered payment plan. It is not a substitute for the official APR in a Truth in Lending disclosure.
Recurring and one-time extra payments
The tool supports both a recurring monthly extra amount and one one-time extra principal payment. It compares that plan with the same financed balance, rate and original term without extras.
A shorter payoff can reduce interest, but the result assumes all extra money is accepted and applied immediately to principal without a penalty.
How to compare loan offers
Do not compare only the monthly payment. Review the amount financed, interest rate, APR, term, fees, total of payments and any optional products. A longer term can lower the payment while increasing total interest.
Use the lender’s disclosures for the final comparison because the legal APR and finance charge depend on transaction-specific definitions and timing.
Loan calculator FAQs
Sources and methodology
Consumer explanations and disclosure context are based on official CFPB materials and Regulation Z.