How to Calculate Loan Payoff Time
This calculator simulates your loan month by month, applying your regular payment plus any extra payment to the balance. It calculates the interest charged each month and shows exactly when the loan will be paid off.
Loan Payoff Formula
Each month, the calculation works as follows:
- Monthly Interest = Remaining Balance x (Annual Rate / 12)
- Principal Payment = Monthly Payment - Monthly Interest
- New Balance = Remaining Balance - Principal Payment
Extra payments are added directly to the principal payment, accelerating payoff.
How to Use This Calculator
- Enter your current loan balance
- Enter the annual interest rate
- Enter your current monthly payment
- Enter any extra amount you can pay per month
The Impact of Extra Payments
Extra payments have a disproportionately large impact early in a loan when the balance is highest. For example, on a $25,000 loan at 5.5% interest with a $500 monthly payment, adding just $100 extra per month saves over $1,700 in interest and pays the loan off 10 months early.
Loan Payoff Calculator FAQ
How do extra payments help pay off a loan faster?
Extra payments go directly toward the principal, reducing the balance that accrues interest. This creates a compounding effect: less principal means less interest, which means more of each subsequent payment goes toward principal. Even small extra payments can save years and thousands in interest.
Should I pay off my loan early or invest?
Compare your loan interest rate to expected investment returns. If your loan charges 5% and you expect 8% from investing, investing may be better mathematically. However, paying off debt provides guaranteed savings and psychological benefits. Many people choose a balanced approach.
Is there a penalty for paying off a loan early?
Some loans have prepayment penalties, especially mortgages from certain lenders. Check your loan agreement before making extra payments. Most personal loans, auto loans, and federal student loans do not have prepayment penalties.
How much should I pay extra on my loan?
Even an extra $50-100 per month can make a significant difference. Use this calculator to experiment with different amounts. A good strategy is to round up to the nearest hundred, or apply any windfalls (bonuses, tax refunds) to your loan principal.
Which debt should I pay off first?
The avalanche method (highest interest rate first) saves the most money. The snowball method (smallest balance first) provides psychological wins. Both are effective. Choose the approach that keeps you motivated.