Find out when your loan will be paid off and how much interest you will pay, and see how much faster extra payments clear the balance.
Advanced: extra and lump-sum payments
Each line tracks the remaining balance month by month. The gap between them is the time and interest the extra payment removes.
For beginners: how to read this result
Start with a preset or enter your own numbers: the current loan balance and the annual interest rate. Then choose how you want the calculator to solve the problem with the mode switch.
Two ways to solve
The mode switch changes which question the calculator answers, and only the field for the active mode stays visible.
- By payment: you enter a monthly payment, and the calculator returns the payoff date and the total interest you will pay. It simulates the loan month by month: the balance grows by one month of interest, the payment is subtracted, and the count runs until the balance reaches zero.
- By date: you enter how many months you want the loan to last, and the calculator returns the level monthly payment required. The required payment equals the balance times the monthly rate, divided by one minus one plus the monthly rate raised to the power of minus the number of months.
Extra and lump-sum payments
The advanced section adds an extra amount paid every month and a single one-time lump-sum payment applied in a chosen month. The savings block compares the plan with these extras against the same payment without them, showing the months and the interest you save. The balance chart draws both paths so the gap between them is easy to see.
The payment must cover interest
Each month interest is charged on the outstanding balance first; only the remainder of the payment reduces what you owe. If a payment is smaller than one month of interest, the balance grows and the loan never clears. The calculator flags this case instead of returning a payoff date.
What is not included
This is an estimate that assumes a fixed interest rate, equal monthly payments and monthly compounding. It does not model daily interest accrual, origination or late fees, rate changes, prepayment penalties or rounding rules used by a specific lender. Check your loan agreement before changing how you pay.