A loan calculator that shows the payoff date and the savings
This loan calculator works out the regular payment on any fixed-rate amortizing loan — a personal loan, auto loan, student loan or small business loan — and shows the total interest, the payoff date and a full amortization schedule. Choose monthly, bi-weekly or weekly payments to match how your lender collects them.
Its real strength is the “Pay it off faster” panel. Add a fixed extra amount to every payment, a one-time lump sum such as a bonus or tax refund, or both, and the calculator compares the result with the original plan: how much interest you save and how many months or years sooner you are debt-free.
It works in dollars, rupees, pounds, euros and other currencies, runs entirely in your browser and needs no sign-up. The figures are estimates for planning, not financial advice — check your loan agreement for fees and prepayment rules.
How to use the Loan Calculator
- Pick how often you pay — Monthly, Bi-weekly or Weekly — and your currency.
- Enter the Loan amount, the annual Interest rate and the Loan term in years or months.
- Optionally add an Extra per payment, a One-time lump sum and the month number in which you will pay it.
- Set the Loan start date so the payoff date and schedule dates are right.
- Read the payment, total interest, payoff date and the interest and time saved by your extra payments.
- Open the schedule by year or by payment and press Download CSV to keep a copy.
Loan Calculator features
Three payment frequencies
Monthly, bi-weekly (26 a year) and weekly (52 a year) payments, each amortized correctly at the matching periodic rate.
Extra and lump-sum payments
Model a recurring overpayment, a one-off prepayment in any month, or both together.
Savings compared side by side
Interest saved and time saved are measured against the same loan without extra payments.
Real payoff date
Dates in the schedule follow your start date, so you know the exact month the loan ends.
Schedule and CSV export
Yearly totals or every single payment, downloadable for Excel or Google Sheets.
Loan payment formula and worked example
For a fixed-rate loan repaid in equal instalments, the payment per period is PMT = P × i ÷ (1 − (1 + i)−N), where P is the amount borrowed, i is the interest rate per period (annual rate ÷ payments per year) and N is the total number of payments. Each payment first covers the interest on the remaining balance; the rest reduces the principal.
Example: $25,000 at 7.5% for 5 years, paid monthly. i = 0.075 ÷ 12 = 0.00625 and N = 60, so the payment is $500.95 and the total interest is $5,056.92. Add $100 extra every month and the loan is cleared after 49 payments instead of 60 — 11 months sooner — and you pay $4,043.31 of interest, a saving of $1,013.61. A single $2,000 lump sum in month 12 instead saves about $661 and five payments.
Bi-weekly vs. accelerated bi-weekly payments
A true bi-weekly loan spreads the same term over 26 payments a year. On the example loan that is $230.89 every two weeks, and the interest falls only slightly, to $5,015.41, because each payment arrives a little earlier.
An accelerated bi-weekly plan is different: you pay half of the monthly payment every two weeks. Because a year has 26 fortnights, that adds up to 13 monthly payments a year instead of 12. To model it, choose Bi-weekly and enter the difference as an extra payment — here $250.47 − $230.89 = $19.58. The loan then ends after 118 payments, roughly six months early, and saves about $490 more interest.
Tips for paying off a loan early
- Check the agreement for prepayment penalties or foreclosure charges first; many personal and auto loans allow free part-payments, some do not.
- Ask the lender to apply extra money to principal, not to future instalments, otherwise it may simply be held as an advance payment.
- Pay off the highest-rate debt first. Card balances usually cost far more than an auto loan — compare them with the credit card payoff calculator.
- For loans quoted as an Indian-style EMI, the EMI calculator gives the same figures with lakh/crore formatting; for a home purchase with taxes and insurance use the mortgage calculator.
Loan Calculator FAQ
How does a loan calculator work out the payment?
It uses the standard amortization formula PMT = P × i ÷ (1 − (1 + i)^−N), with the interest rate and number of payments matched to your payment frequency. Each payment pays the interest due first and the remainder reduces the balance.
How much interest do extra payments save?
It depends on the rate and how early you start. Every extra dollar reduces the balance immediately, so it stops earning interest for the rest of the term. On a $25,000 loan at 7.5% over 5 years, $100 a month extra saves about $1,014 and 11 months.
Is it better to make one lump sum or regular extra payments?
Money paid earlier saves more interest, so a lump sum early in the loan is very effective. Regular extra payments add up over time and are easier to budget. Try both in the calculator to compare.
Why does my lender’s figure differ slightly from this loan calculator?
Lenders may count interest daily, round each payment to the cent, add fees to the balance or use a different first-payment date. The difference is usually a few cents to a few dollars; treat these results as estimates.
Do bi-weekly payments really save money?
True bi-weekly payments save a little because money arrives earlier. The bigger saving comes from accelerated bi-weekly plans that make the equivalent of one extra monthly payment each year.
Can I use this for a car loan or a student loan?
Yes. Any fixed-rate loan repaid in equal instalments works — auto, student, personal, boat or equipment loans. Variable-rate loans change over time, so recalculate whenever your rate changes.