Payment Calculator
Given the amount borrowed, rate and a target monthly payment, find the payoff time and total interest.
Runs 100% in your browser — nothing is uploaded.
Result
Formula
n = ln(pmt ÷ (pmt − P·r)) ÷ ln(1 + r)
About this calculator
The Payment Calculator determines how long it will take to pay off a loan when you know the loan amount, the annual interest rate, and the fixed monthly payment you can afford. It also calculates the total interest and total amount paid over the life of the loan.
How to use
- 1
Enter the loan amount you borrowed.
- 2
Input the annual interest rate as a percentage.
- 3
Set your target monthly payment and click Calculate.
Frequently asked questions
What happens if my monthly payment is less than the monthly interest?
If the payment is less than or equal to the monthly interest, the loan will never be paid off because the payment does not cover the interest accruing each month. The calculator will show an error message asking you to increase your payment.
Why does the payoff time show both years/months and total payments?
The years and months format is easier to visualize, while the total number of payments is useful for comparing with the original loan term or for budgeting.
Can I use this calculator for any type of loan?
Yes, as long as the loan has a fixed interest rate and fixed monthly payments, such as auto loans, personal loans, or student loans. It is not suitable for credit cards with variable minimum payments or interest-only loans.
Please note: Results are estimates for general information only and are not professional or medical/financial advice.