Free calculator
Interest-Only Loan Calculator
This interest-only loan calculator shows what you pay during the interest-only phase and what the payment becomes once principal repayment begins.
The lowest rates are only available to the most qualified applicants.
Advertising disclosure: Loancalculated may receive a referral fee if you apply through the link above. That fee does not change the rate you are offered, and it does not change our content. We are not a lender. Read the full disclosure.
Enter your numbers and press Calculate. Nothing you type leaves your browser.
The lowest rates are only available to the most qualified applicants.
Advertising disclosure: Loancalculated may receive a referral fee if you apply through the link above. That fee does not change the rate you are offered, and it does not change our content. We are not a lender. Read the full disclosure.
How this calculator works
During an interest-only period you pay just the interest, so the balance does not fall. Once that period ends, the loan is amortized over the months that remain.
Interest-only payment = P × i, where i is the annual rate ÷ 1,200.
After the interest-only phase: Payment = P × i ÷ (1 − (1 + i)−m), where m is the number of months left.
- P — the amount borrowed
- i — the monthly rate
- m — remaining months after the interest-only period
Total interest is the interest paid during the interest-only phase plus the interest paid during repayment. If the interest-only phase spans the whole term, the principal is due as a balloon.
Rates are user inputs here; pricing varies by lender and state.