Loan Interest Calculator
See the total interest a loan costs and what drives that number.
Total loan interest is everything you pay above the amount you borrowed. It grows with a higher rate and a longer term. On a $25,000 loan at 7.5% over 5 years you pay about $5,053 in interest; stretch the same loan to 7 years and interest climbs past $7,000. Enter your loan to see the total and how it changes.
These results are estimates for informational purposes only and are not financial, tax, or legal advice. Your actual figures from a lender or the IRS may differ. Consult a qualified professional before making decisions.
Estimated monthly payment
$500.95
Principal vs. interest paid per year
Amortization schedule
| Year | Principal | Interest | Balance |
|---|---|---|---|
| 1 | $4,282 | $1,730 | $20,718 |
| 2 | $4,614 | $1,397 | $16,104 |
| 3 | $4,972 | $1,039 | $11,132 |
| 4 | $5,358 | $653 | $5,774 |
| 5 | $5,774 | $237 | $0 |
About the Loan Interest Calculator
Where a payment calculator answers what you owe each month, this tool focuses on the number borrowers underestimate most: the interest you pay across the whole loan. It is the difference between the total of all your payments and the amount you originally borrowed, and it is sensitive to both the rate and the term. Raising the rate increases interest in a straight line, but the term is sneakier. Each extra year keeps a balance outstanding longer, so interest compounds against you well after the monthly payment has stopped feeling painful. The schedule below makes the pattern concrete. In the opening months almost all of your payment is interest because it is charged on the full balance, and only later does principal take over. That front-loading is why paying extra early, when the balance is largest, removes far more interest than the same dollar paid near the end. Compare two loans by total interest rather than monthly payment to see which one is actually cheaper.
Frequently asked questions
How is total loan interest calculated?+
Add up every monthly payment over the life of the loan, then subtract the amount you borrowed. What remains is the total interest. This calculator does that automatically from your amount, rate, and term.
Does a longer term mean more interest?+
Yes. A longer term lowers the monthly payment but keeps the balance outstanding for more months, so interest accumulates longer. The same loan over seven years can cost far more interest than over five, even at an identical rate.
Why is so much early payment interest?+
Interest is charged on the outstanding balance, which is highest at the start. So early payments are mostly interest and little principal. As the balance falls, the interest portion shrinks and principal grows, even though the payment is fixed.
How do I pay less interest overall?+
Choose a lower rate, a shorter term, or pay extra toward principal, especially early when the balance is large. Even small additional payments in the first years cut total interest more than the same amount paid later.