Loan Payoff Calculator
Estimate your loan payoff date, total interest, and how extra payments can help you pay off debt faster.
Loan payoff inputs
Enter your current loan balance, interest rate, payment, and any extra payments.
Outstanding loan balance today.
Annual rate applied to the loan balance.
Your usual payment per period (monthly, biweekly, or weekly).
Optional extra amount applied to principal every period.
Optional lump-sum applied at the first payment period.
How often you make a payment.
Estimated payoff date
Jul 2030
Based on your current payment and any extra payments.
Time to payoff
4y 1m
49 monthly payments.
Total interest
£4,051
Estimated interest paid until payoff.
Interest saved
£1,018
Compared with current payment only.
Time saved
1 year
Compared with current payment only.
Total amount paid
£29,051
Sum of all payments and extras.
Total extra payments
£4,800
Extras applied across all periods.
First-period interest
£156
Approximate interest for the first monthly period.
Payoff scenario comparison
| Scenario | Payment | Extra | Time to payoff | Total interest | Total paid | Interest saved |
|---|---|---|---|---|---|---|
| Current payment only | £500 | £0 | 5y 1m | £5,069 | £30,069 | £0 |
| With extra payments | £500 | £100 | 4y 1m | £4,051 | £29,051 | £1,018 |
Payoff schedule
Support
Loan payoff support layer
Payment formula
Each period, interest is calculated on the current balance. Anything above interest reduces the principal.
Estimate only
Results are estimates. Fees, prepayment rules, and daily interest accrual can change exact figures.
Extra payment impact
Extra payments directly cut principal, lowering interest charged in every remaining period.
Interest savings
Compare current payment only against the extra-payment scenario to see how much interest you avoid.
Loan payoff basics
What is a loan payoff calculator?
A loan payoff calculator estimates how long it will take to clear a loan from where you are today, how much interest you will pay along the way, and how extra payments can shorten the journey. Unlike a Loan Calculator that designs a brand new repayment schedule, this tool focuses on payoff strategy for an existing balance.
Balance
The amount currently owed. Interest is charged on the unpaid balance each period.
APR
The annual interest rate, converted to a periodic rate based on your payment frequency.
Payment
The amount paid each period. The portion above interest reduces principal.
Extra payment
Any amount above the scheduled payment goes straight to principal.
How it works
How this loan payoff calculator works
Period-by-period simulation
The calculator loops through each payment period, applies interest, subtracts the payment plus any extras, and stops when the balance reaches zero.
Baseline comparison
In parallel, it simulates the same loan without extra payments. The difference shows your interest saved and time saved.
Safety checks
If your payment cannot cover interest and there are no extra payments, the calculator warns you instead of running forever.
Frequency aware
Monthly, biweekly, and weekly schedules each use their own periodic rate, so payoff time reflects how often you actually pay.
Formula
Loan payoff formula
Periodic interest
Interest = Balance × (APR ÷ periods per year)Each period, interest is added to the loan before your payment is applied.
Balance update
New Balance = Balance + Interest − Payment − ExtraWhatever is left after interest goes to principal, including any extra payment.
Payoff condition
Loop until Balance ≤ 0 or warning shownThe schedule ends when the balance is cleared. If the payment is too small, the warning fires.
Strategy
How extra payments reduce interest
Because interest is charged on the remaining balance, anything that lowers the balance lowers every future interest charge as well. A small recurring extra payment can compound into thousands in savings over a long loan, and a single well-timed lump-sum at the start of the loan removes interest on that amount for every remaining period.
Frequency
Monthly vs biweekly payoff
Monthly payments
Twelve payments a year. Easiest to align with most paychecks and billing cycles.
Biweekly payments
Twenty-six payments a year. Equivalent to roughly one extra monthly payment each year, which can shorten payoff time on long loans.
Limits
When a loan may not be paid off
If the periodic interest is greater than your payment, the balance stays flat or grows. This is most common with high-APR loans paid at minimum levels. To make progress, increase the payment, lower the rate (for example via refinancing), or add an extra payment so the principal can shrink.
Caveats
Limitations of this estimate
Fees and charges
Lender fees, late charges, and prepayment penalties are not modeled here.
Daily interest
Some loans use daily interest accrual. This calculator uses periodic accrual aligned to your payment frequency.
Variable rates
If your APR changes during the loan, the actual payoff may differ from this estimate.
Not advice
This calculator is educational. Review your loan agreement and lender terms before making decisions.
FAQ
Loan payoff calculator questions
Enter your current balance, interest rate, regular payment, and payment frequency. The calculator simulates each payment period, applies interest, subtracts your payment, and reports the period in which the balance reaches zero.
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