Debt Payoff Calculator

Find out exactly how long until you're debt free — and how much extra payments save.

Months to Payoff
—
Total Interest Paid
—
$
Total Amount Paid
—
$
Payoff Date
—

Extra Payment Saver

Move the slider to see savings.

How the Debt Payoff Calculator Works

This calculator uses the standard loan amortization formula to determine how many months it will take to pay off a balance at a fixed interest rate and monthly payment. The formula is: months = −log(1 − balance × monthly rate ÷ payment) ÷ log(1 + monthly rate). Total interest paid equals total amount paid minus the original balance. The payoff date is projected from today's date. The extra payment slider recalculates everything in real time — you can instantly see how paying even $50 more per month can shave months off your timeline and save hundreds in interest. If your monthly payment is less than the monthly interest charge, the balance will never decrease and a warning is shown.

Frequently Asked Questions

How do I calculate how long it will take to pay off debt?
Use the formula: months = -log(1 - balance×rate/payment) ÷ log(1+rate). Or use this calculator and enter your balance, APR and monthly payment.
Does paying extra on principal reduce interest?
Yes — significantly. On a $10,000 balance at 18.99% APR, paying $50 extra per month can save over $1,500 in interest.
What is a good monthly payment for $10,000 of debt?
Aim to pay it off within 36 months. For $10,000 at 18.99%, that's about $365/month. The minimum payment would take over 10 years.
Should I pay off the lowest balance or highest interest first?
Highest interest first (avalanche) saves the most money. Lowest balance first (snowball) provides faster psychological wins.

Related Tools

Debt Snowball Calculator Markup Calculator Dividend Yield Calculator