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Debt Payoff Calculator

Find out when you could be debt-free and how much time and interest an extra monthly payment could save.

How it works

Enter your current balance, annual interest rate, your regular monthly payment and any extra amount you could add.

Each month interest is added at the annual rate ÷ 12 and your payment is subtracted until the balance reaches zero. The calculator runs this twice — with and without the extra payment — to compare.

Actual lender calculations may differ, for example due to daily interest, minimum payment rules or new charges.

Formula & methodology

Balanceₜ₊₁ = Balanceₜ × (1 + r) − Payment
r
Monthly interest rate (APR ÷ 12)
Payment
Monthly payment (+ extra payment)

Your payment must be larger than the first month's interest, or the balance would never fall.

This assumes no new charges are added to the balance.

Illustrative example

$10,000 at 18% APR

Paying $300 a month takes about 47 months and costs about $3,967 in interest.

Adding $100 a month cuts that to about 32 months and roughly $2,628 in interest.

Hypothetical figures for illustration only.

Frequently asked questions

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