How many months until this loan is somebody else's problem? Exactly this many.
Use this free loan payoff calculator to find out how many months are left on any loan. Enter the current balance, your monthly payment, and the interest rate, and get the number of months until the balance hits zero — for car loans, student loans, personal loans, and anything else with an amortization schedule.
The useful trick here is running it twice. Once with your current payment, once with an extra $100. The gap between those two numbers is what procrastination costs, expressed in months of your life.
What This Loan Payoff Calculator Does
- Calculates months remaining from balance, payment, and rate
- Works with any fixed-rate installment loan — auto, student, personal, consolidation
- Lets you test extra payments by raising the payment and recalculating
- Uses the same amortization math your lender uses, so the answers match your statement
How to Use the Loan Payoff Calculator
Inputs:
- Balance — current payoff balance, not the original loan amount
- Payment — what you pay per month, including any extra you send toward principal
- Rate — annual interest rate in %
Steps:
- Enter your current balance from the latest statement
- Enter your monthly payment and the annual rate
- Click Calculate for months remaining
- Add $50 or $100 to the payment and calculate again — write down the difference before you talk yourself out of it
How the Calculation Works
n = −ln(1 − r × B ÷ P) ÷ ln(1 + r)
r = Rate ÷ 12 ÷ 100 · B = balance · P = monthly payment
- Total interest remaining = P × n − B
- If P ≤ B × r, the payment is smaller than one month of interest and the loan never ends — the formula breaks down for a reason
- Extra payments apply to principal, which is why they shorten the term much faster than they lower the balance
- Assumes a fixed rate and no fees. Some lenders charge prepayment penalties — check before making a lump-sum payment
Worked Example: $18,000 balance, $420/month, 7% APR
- r = 0.07 ÷ 12 = 0.005833 · r × B = $105 of the first payment is interest
- n = −ln(1 − 0.005833 × 18,000 ÷ 420) ÷ ln(1.005833) = −ln(0.75) ÷ 0.005816 = 49.4 → 50 months
- Total paid ≈ 420 × 49.4 = $20,748 → interest = $2,748
- At $520/month: 38 months and about $2,080 of interest. The extra $100 buys back a year and saves $668. Same loan, different decision.
Tips (From People Who Have Made These Mistakes)
- Round payments up to a clean number ($420 → $450). It feels like nothing and behaves like an extra payment every year
- Paying biweekly (half the payment every two weeks) produces 13 monthly payments a year instead of 12 — roughly a year off a five-year loan
- Attack the highest rate first when juggling several loans; use the credit card payoff calculator for revolving debt
- Confirm extra payments are applied to principal and not held as a prepaid future installment. Lenders do both
Frequently Asked Questions
How do I calculate how long to pay off a loan?
Use n = −ln(1 − rB/P) ÷ ln(1 + r), where r is the monthly rate, B the balance, and P the payment — or enter the three numbers above. $10,000 at 6% with $300/month is 37 months.
How much faster will an extra payment pay off my loan?
Far more than the ratio suggests, because every extra dollar skips all the future interest on that dollar. On a typical 5-year auto loan, an extra 20% per month cuts about a year off the term.
Should I pay off a low-interest loan early?
Mathematically, no — if the rate is below what savings or investments return, the money works harder elsewhere. Psychologically, being debt-free has value the spreadsheet cannot price. Both answers are defensible under 4%.
Why is my payoff amount higher than my balance?
Payoff quotes include interest accrued since your last payment plus any fees. The gap is usually a few days of interest, which is why quotes are only valid to a stated date.
Does the calculator work for student loans?
Yes for standard fixed-rate repayment. Income-driven plans, subsidies, and forgiveness programs change the math entirely and need your servicer's numbers.
Mini Roast Disclaimer
We roast the number, not you. Fifty months sounds long until you remember the loan is already 22 months old and you never checked.
Reality Check
Assumes a fixed rate, a constant payment, and no fees or prepayment penalties. Variable rates, deferrals, and late fees all move the finish line. Get the exact payoff figure from your lender before sending a final payment — being $12 short keeps the loan open.