Loan calculator
Enter a loan amount, interest rate and term to see your monthly payment, the total you will repay, and how much of that is interest. Everything is calculated instantly in your browser.
How to use Loan Calculator
- 1
Enter the loan amount
Type how much you plan to borrow.
- 2
Add the interest rate and term
Enter the annual interest rate and the length of the loan in years.
- 3
Read your payment
See the monthly payment, total repaid and total interest instantly.
- 4
Compare options
Adjust the inputs to see how amount, rate and term change the cost.
Know your monthly payment before you borrow
The single most important number when taking on a loan is the monthly payment, because that is what has to fit into your budget month after month. This calculator works it out for you using the standard amortization formula that banks and lenders use, based on three inputs: how much you are borrowing, the annual interest rate, and the length of the loan in years. The moment you enter them, you see the monthly payment, so you can judge immediately whether a loan is affordable before you commit to anything. This works for the loans people most commonly take out — personal loans, car loans and mortgages all use the same underlying math — so whether you are sizing up a vehicle purchase, a home loan or a personal borrowing need, the calculator gives you a realistic figure. Knowing the payment up front lets you shop with confidence, compare offers on an equal footing, and avoid the unpleasant surprise of agreeing to a loan whose repayments turn out to be more than you expected.
See the true cost, not just the payment
A low monthly payment can be misleading, because stretching a loan over more years reduces the monthly figure while quietly increasing the total amount you pay. That is why this calculator shows more than just the payment. It also reveals the total of all payments over the life of the loan and, crucially, how much of that total is interest rather than the amount you actually borrowed. Seeing the interest figure laid out plainly is often eye-opening: it is the real price of borrowing, and it can be a substantial fraction of the loan itself, especially at higher rates or over longer terms. With these numbers in front of you, you can make a genuinely informed decision rather than fixating on the monthly payment alone. It becomes obvious how much a longer term really costs, or how much a slightly lower interest rate saves over the years, which is exactly the perspective you need when comparing loan offers that differ in rate and length.
Compare scenarios instantly
Choosing a loan is rarely about one set of numbers; it is about weighing options. What does the payment look like if you borrow a bit less? How much would a shorter term save in interest, and can you afford the higher monthly cost? How much difference does a one-point change in the interest rate actually make? Because this calculator updates the instant you change any input, you can answer these questions in seconds, adjusting the amount, rate or term and watching all the figures respond together. This makes it easy to find the balance that works for you — a payment you can comfortably afford while keeping the total interest as low as you reasonably can. Instead of running each scenario through a formula by hand or filling in a lender's form repeatedly, you explore the trade-offs live. That interactive comparison is where the real value lies, turning a single calculation into a tool for genuinely understanding the shape of a borrowing decision before you make it.
Private by design — calculated in your browser
The numbers behind a loan are personal: how much you earn, what you can afford, what you are planning to buy. There is no reason to send any of that to a server just to do arithmetic, and good reason to keep it to yourself. In1 performs the entire loan calculation locally in your browser. The amount, rate and term you enter never leave your device — nothing is uploaded, nothing is stored, and there is no account or sign-up that ties these figures to you. The results appear instantly because there is no network round trip, and the calculator works exactly the same offline as online. This local-only approach means you can model a sensitive borrowing decision in complete privacy, without registering your financial situation with any website. It is the convenience of an online calculator with the discretion of working it out on paper, which is the right standard for a tool that handles the numbers behind one of the bigger financial commitments most people make.
An estimate to guide you, not a quote
It helps to be clear about what this calculator is and is not. It gives you a sound estimate of the principal-and-interest payment using the standard amortization formula, which is exactly the right tool for planning, budgeting and comparing offers. What it does not include are the extras that vary by loan and lender: things like origination fees, insurance, property taxes that may be bundled into a mortgage payment, or the effect of an introductory or variable rate that changes over time. Those depend on your specific lender and situation, so a real quote may differ. Treating the result as a reliable guide rather than a binding figure is the right way to use it — it tells you the core cost of the borrowing and lets you compare loans on a consistent basis, while you confirm the final details with the lender. Used that way, it is genuinely useful: it puts you in a far stronger position to understand and negotiate a loan than walking in with no numbers at all.
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