Loan Calculator
Calculate the monthly payment on any fixed-rate loan, plus the total interest, total cost, and payoff time. Add an optional extra monthly payment to see how much interest you save and how many months you shave off — works for auto, personal, student, and other installment loans.
How to Use
- Enter the loan amount (the principal you are borrowing).
- Enter the annual interest rate as a percent.
- Enter the loan term in years.
- Optionally add an extra monthly payment to accelerate payoff.
- Read the monthly payment, total interest, total paid, and payoff time — including the savings from any extra payments.
Show Work
Formula
About the Loan Calculator
Whether you are at a desk or on your phone, the Loan Calculator makes personal-finance and money decisions easy — and it is completely free. Calculate the monthly payment on any fixed-rate loan, plus the total interest, total cost, and payoff time. Add an optional extra monthly payment to see how much interest you save and how many months you shave off — works for auto, personal, student, and other installment loans.
How it works
Type your numbers into the boxes. The answer shows up right away — you do not have to press a button. If you change a number, the answer changes too. So you can try different numbers and watch what happens, or check an answer you worked out yourself. Just make sure each box has the right kind of number in it.
Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.
Frequently Asked Questions
How is my monthly loan payment calculated?
A fixed-rate loan uses the amortization formula: payment = P · r(1+r)^n / ((1+r)^n − 1), where P is the principal, r is the monthly rate (annual rate ÷ 12), and n is the number of monthly payments. Each payment is level, but early payments are mostly interest and later ones mostly principal.
How much do extra payments save me?
Extra payments go straight to principal, shrinking the balance that interest is charged on. Even a modest amount each month can cut months or years off the loan and save meaningful interest. Enter an extra-payment figure and the tool shows the new payoff time and the reduced total interest.
What is the difference between interest rate and APR?
The interest rate is the cost of borrowing the principal. APR also rolls in certain fees (origination, points) expressed as an annual rate, so it is usually equal to or higher than the rate. When comparing loan offers, APR is the fairer apples-to-apples number. This calculator uses the plain interest rate you enter.
Does this work for any kind of loan?
It works for any fixed-rate, fully amortizing installment loan — auto, personal, student, or a basic mortgage. It does not model variable rates, interest-only periods, balloon payments, or escrow items like property tax and insurance. For a full home payment, use the Mortgage calculator.
Why does so much of my early payment go to interest?
Interest each month is charged on the remaining balance, which is highest at the start. So early payments are interest-heavy and principal-light; as the balance falls, the split gradually flips toward principal. This is why paying extra early in the loan has the biggest impact.
How do I use the Loan Calculator?
Just type your numbers. The answer shows up right away — there is no button to press. Change anything and it updates by itself.
Is it free? Does it work without internet?
Yes to both. It is free with no sign-up, and once the page has loaded it keeps working even with no internet.
Where does my data go?
Nowhere — every calculation runs on your own device. Nothing you enter is uploaded, logged, or stored.
Common Use Cases
Pricing a car or personal loan
Find the monthly payment for a given amount, rate, and term before you sign with a lender.
Comparing loan terms
Weigh a shorter term with higher payments against a longer term with more total interest.
Planning an early payoff
See how adding $50, $100, or more per month shortens the loan and slashes total interest.
Budgeting before you borrow
Confirm the monthly payment fits your budget and check the true total cost over the life of the loan.
Estimating student loan repayment
Project payments and total interest on a fixed-rate student loan across a standard repayment term.
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