Loan calculator
Find the payment, the interest, and the day the debt ends.
Payment every month
$1,110.21
| Year | Interest | Principal | Ending balance |
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How an amortized loan payment is set
Most personal, auto and student loans are amortized: the payment stays the same every month, but its makeup changes. Early payments are mostly interest, because interest is charged on a large balance. As the balance falls, the same payment covers less interest and more principal, so the debt shrinks faster near the end. The payment itself comes from the formula below, which spreads the loan evenly across the whole term.
Check it against the defaults on this page. A $100,000 loan at 6% for ten years gives a monthly payment of $1,110.21. Across 120 payments that is $133,224.60 paid in total, of which $33,224.60 is interest. Roughly a quarter of everything paid goes to the lender rather than to the balance, which is why the term matters so much: stretch the same loan to twenty years and the payment falls, but the interest bill grows far more than the payment shrinks.
Extra payments attack the schedule at its weakest point. Any amount added on top of the set payment goes entirely to principal, because the interest for that month is already covered. A smaller balance next month means less interest, which means even more of the following payment reaches principal. The optional extra payment field above shows the effect directly: the payoff count drops and the interest total falls, often by thousands on a long loan.
Two terms decide what a quoted loan really costs. The interest rate is the price of borrowing the balance. The APR wraps that rate together with lender fees into one yearly figure, so APR is the fairer number for comparing offers. A loan with a lower rate but heavy fees can carry the higher APR, and cost more.
Frequently asked questions
How is a monthly loan payment calculated?
The payment is set so that equal monthly payments exactly retire the loan on schedule: payment = P x r(1+r)n / ((1+r)n - 1), where P is the amount borrowed, r the monthly rate and n the number of payments. Early payments are mostly interest; later ones mostly principal.
What does a $100,000 loan at 6% for 10 years cost per month?
The payment is $1,110.21 a month. Over the 10 years you repay $133,224.60 in total, of which $33,224.60 is interest on top of the $100,000 borrowed.
Do extra monthly payments actually save much?
Yes, because every extra dollar goes straight to principal and stops interest accruing on it. On the $100,000 example above, an extra $200 a month ends the loan 23 months early and saves $6,958.80 of interest.
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Estimates only. Lenders may add fees, and payment dates and rounding can shift totals slightly; this tool is not financial advice.