The Repayment Calculator works out the periodic payment needed to repay a loan over a fixed term, or how long it will take to repay a loan when you make a fixed payment each period. It also shows the total of all payments and the total interest.
The repayment calculator answers the two questions borrowers ask most often about a loan. First: how much do I have to pay each period to clear this loan in a set amount of time? Second: if I can afford a certain payment, how long will it take to pay the loan off? Enter your loan amount, interest rate, and how the loan compounds and is repaid, then choose whichever of the two methods fits your situation. The calculator returns the payment (or the payoff time), the total of all payments, and the total interest you will pay along the way.
It works for almost any kind of installment loan — personal loans, auto loans, student loans, mortgages, and more — because they all share the same underlying math. Understanding that math puts you in control: you can see exactly how the term, the rate, and the payment size trade off against one another, and how much interest each choice really costs.
With this method you tell the calculator how long you want to take to repay the loan — say five years — and it computes the fixed payment required each period to clear the balance exactly on schedule. This is how most conventional loans are structured: you agree to a term, and the lender sets a level payment that covers both interest and principal so the loan reaches zero at the end.
Using the calculator's defaults — a $10,000 loan at 10% compounded monthly, repaid monthly over 5 years — the required payment is about $212.47 per month. Over 60 payments that totals $12,748.23, of which $2,748.23 is interest.
Here you tell the calculator how much you can pay each period, and it works out how long the loan will take to disappear. This is the useful view when you have a budget in mind: you know you can put, say, $200 a month toward the loan, and you want to know when you will be free of it. Paying $200 a month on that same $10,000 loan clears it in about 5 years and 5 months, with slightly more total interest than the 5-year fixed term because the payoff stretches a little longer.
Comparing the two methods side by side reveals the central lever of any loan: bigger payments mean a shorter term and less total interest; smaller payments mean a longer term and more interest.
An installment loan is repaid with a series of equal payments. Each payment first covers the interest accrued that period, and whatever is left reduces the principal. Early on, most of each payment goes to interest; as the balance falls, more goes to principal. This process is called amortization.
The payment for a fixed term is found with the standard amortization formula:
Payment = P × r ÷ [ 1 − (1 + r)−n ]
where P is the loan amount, r is the interest rate per payment period, and n is the total number of payments. When you fix the payment instead and solve for the term, the same relationship is rearranged to find n using logarithms.
One subtlety that trips people up is the difference between how often a loan compounds and how often you pay it. These are not always the same. A loan might compound monthly but be paid biweekly, for example. The calculator lets you set both independently and converts the stated rate into the correct rate per payment period, so the result is accurate regardless of the combination.
This is also where the distinction between APR and APY shows up. A rate compounded annually is an APY (annual percentage yield), while the same nominal rate compounded monthly is quoted as an APR (annual percentage rate). Because compounding adds interest on interest, more frequent compounding makes a loan slightly more expensive for the same stated rate. The calculator handles the conversion for you.
Three inputs determine how much interest you ultimately pay:
The tension between monthly affordability and total cost is the heart of every borrowing decision. Stretching a loan out makes each payment easier but can dramatically increase what you pay overall; paying it down faster costs more each month but far less in the end.
The word "amortize" comes from a root meaning "to kill off" — and that is exactly what a repayment schedule does to a loan balance, one payment at a time. Each level payment is split into two parts: the interest owed on the current balance, and a principal portion that pays down the debt. Because interest is charged on the outstanding balance, and that balance is largest at the start, your early payments are mostly interest and only a little principal. As the balance shrinks, the interest portion falls and the principal portion grows, even though the total payment stays the same.
This front-loading of interest has real consequences. It is why paying a little extra early in a loan's life saves so much more interest than the same extra payment made near the end — early extra principal removes balance that would otherwise have accrued interest for the entire remaining term. It is also why, a few years into a long mortgage, borrowers are often surprised how little of their balance they have actually paid off despite years of payments. Understanding the amortization curve turns those surprises into informed decisions.
The loan term is the most powerful lever you control, and it forces a genuine trade-off. A longer term spreads the balance over more payments, so each payment is smaller and more affordable month to month. But you hold the debt longer and pay interest on it the whole time, so the total cost is higher — sometimes dramatically so on large, long loans. A shorter term flips this: higher payments, but far less total interest and freedom from the debt sooner.
There is no universally correct answer; it depends on your budget and priorities. A useful way to decide is to run both scenarios through the calculator and look at the total interest for each. Seeing that, say, stretching a loan from a shorter to a longer term saves a modest amount per payment but costs thousands more overall often reframes the decision. Many borrowers choose a term whose payment they can comfortably afford, then use the fixed-payment view to see how paying a bit extra shortens the real payoff.
Because every amortizing installment loan shares the same underlying math, this calculator works across a wide range of borrowing:
What the calculator does not cover are loans structured differently — interest-only loans, balloon loans, credit cards with revolving balances and minimum payments, or loans with variable rates that change over time. For a standard fixed-rate installment loan, though, the numbers here reflect exactly how the loan behaves.
One of the most useful things this calculator reveals is the total interest — the true cost of borrowing, separate from the amount you borrowed. On a short, low-rate loan this may be a small fraction of the principal; on a long, high-rate loan it can approach or even exceed the principal itself. Making that number visible before you sign is one of the best defenses against underestimating what a loan really costs. Whenever you compare loan offers, comparing total interest — not just the monthly payment — gives you the honest picture, because a lower payment achieved by stretching the term can hide a much larger total cost.
This calculator assumes a fixed interest rate — one that stays the same for the entire life of the loan — which is the most common structure for personal, auto, and many mortgage loans. A fixed rate makes budgeting easy because every payment is identical and the total cost is known in advance, exactly as the calculator shows. Some loans instead carry a variable or adjustable rate that changes over time with market conditions. With those, the payment or the payoff time can shift as the rate moves, so a single calculation only reflects the current rate. If your loan is variable, treat the result here as a snapshot based on today's rate, and recalculate whenever the rate changes to see the new payment or timeline. When comparing a fixed offer against a variable one, it helps to model the variable loan at both its starting rate and a higher rate to understand the range of outcomes you might face.
The fixed-term method asks how long you want to take and computes the required payment. The fixed-payment method asks how much you can pay each period and computes how long the loan will take to pay off. They are two views of the same loan.
In the default example, the fixed $200 payment is slightly smaller than the payment a 5-year term would require, so the loan takes a little longer to clear and accrues a bit more interest. Larger payments always shorten the term and reduce total interest.
It is how often interest is added to the balance. More frequent compounding makes a loan slightly more expensive for the same stated rate. The calculator converts between your compounding frequency and your payment frequency automatically.
Yes. Any amortizing installment loan — mortgage, auto, personal, or student loan — uses this same math. Enter the loan amount, rate, and repayment details for your specific loan.
Pay more than the minimum, pay more frequently, choose a shorter term, secure a lower rate, or borrow less. Each of these reduces either the balance or the time you carry it, which lowers total interest.
No. It calculates principal and interest only. Real loans may add origination fees, insurance, taxes, or other charges that increase the total cost, so treat the result as the core loan math rather than the full picture.
This Repayment Calculator is provided for educational and general informational purposes. It computes principal and interest for an amortizing loan and does not include fees, insurance, taxes, or other charges that may apply. Actual loan terms vary by lender. Consult your lender and a qualified financial professional before making borrowing decisions.