Loan Payment Calculator
Estimate the monthly payment, total interest, and payoff time for an auto loan, personal loan, or other fixed-rate installment loan. Add extra payments to see how much time and interest you could save.
Model a loan
Amount financed, up to $10,000,000.
Use a rate from 0% through 40%.
Common auto and personal loan terms.
Paying this amount pays off the loan in 60 months (5 years), including $5,642.16 in interest.
- Total interest
- $5,642.16
- Total paid
- $35,642.16
- Payoff time
- 60 months (5 years)
What if you pay more each month?
How a loan payment is calculated
This calculator uses the standard fixed-rate, level-payment amortization formula. Each month, part of the payment covers interest on the remaining balance and the rest reduces principal. As the balance shrinks, more of each payment goes toward principal.
M = P × r(1 + r)n / ((1 + r)n − 1)- M
- Monthly payment
- P
- Loan amount (principal)
- r
- Monthly interest rate (annual rate ÷ 12)
- n
- Number of monthly payments (loan term)
An optional extra monthly payment is applied directly to the remaining principal on top of the required payment. Because future interest is charged only on the remaining balance, consistently paying extra reduces both the total interest paid and the number of months needed to pay off the loan.
$30,000 loan at 7% for 60 months
A $30,000 loan at a 7% fixed annual interest rate with a 60-month term produces an estimated monthly payment of $594.04. Over the full 60-month term, total interest comes to $5,642.16, for a total amount paid of $35,642.16.
This is an educational estimate. Actual loan offers depend on the lender, your credit profile, fees, and other terms not modeled here.
What this calculator assumes
- The interest rate is fixed for the entire loan term.
- No origination fees, taxes, or other charges are modeled.
- Any extra monthly payment is applied entirely to principal.
- Payments are made monthly, with interest compounding monthly.
- Money values are rounded to the nearest cent for display.
Understanding the Loan Payment Calculator
Most consumer borrowing — car loans, personal loans, debt consolidation, home-improvement financing — is a fixed-rate installment loan: you borrow a set amount and repay it in equal monthly payments over a fixed term. This calculator turns the three numbers a lender quotes you (amount, rate, and term) into the payment you will actually make, plus the total interest that borrowing will cost.
It is built to make the tradeoffs visible: how a longer term lowers the payment but raises total interest, how a lower rate helps, and how adding even a small extra payment each month can shorten the loan and cut the interest you pay.
Who this calculator is for
- Personal loan shopperswho want to compare offers and know the real monthly payment before signing.
- Car and big-purchase buyerssizing a fixed-rate installment payment against a monthly budget.
- Debt consolidatorschecking whether a single fixed-rate loan beats their current mix of balances.
- Extra-payment plannersseeing how much time and interest a recurring extra payment can save.
- Careful budgeterscomparing term lengths to balance an affordable payment against lifetime cost.
Why it matters
- It gives you the true monthly payment, so you can check it against your budget instead of guessing from the loan amount alone.
- It exposes the total interest, which is the real price of borrowing and the number lenders rarely lead with.
- It makes the term-length tradeoff concrete: a longer term shrinks the monthly payment but almost always increases total interest.
- It quantifies extra payments, showing how a modest recurring amount can knock months or years off the loan and save real interest.
- It works across auto, personal, and other fixed-rate installment loans, so one tool covers most everyday borrowing decisions.
How to use this calculator
- Enter the loan amount — the principal you are borrowing after any down payment or fees you are paying separately.
- Enter the annual interest rate. If you only have an APR, it is a reasonable input here, though APR can also fold in certain fees (see the FAQ).
- Set the term in months (for example 36, 48, or 60). A longer term lowers the payment but raises total interest.
- Optionally add an extra monthly payment to apply directly to principal.
- Read the monthly payment, total interest, and payoff timeline, and adjust any input to compare scenarios instantly.
How to read your result
The headline figure is your level monthly payment — the same amount every month for the whole term. Early on, most of each payment goes to interest and only a little to principal; as the balance falls, that flips and more of each payment reduces what you owe. That is why paying extra early has an outsized effect.
The number that deserves equal attention is total interest. Two loans with a similar monthly payment can cost very different amounts overall if their terms differ, because a longer term means more months of interest. Use the calculator to weigh a comfortable payment against the total cost, rather than optimizing for the monthly figure alone.
- The rate you enter is assumed fixed for the entire term. Variable-rate loans and promotional teaser rates can change, which this calculator does not simulate.
- This tool models principal and interest only. Origination fees, late fees, insurance add-ons, and prepayment penalties are not included and can raise your real cost.
- A lower monthly payment from a longer term is not the same as a cheaper loan. Stretching the term usually increases the total interest you pay, sometimes substantially.
- The interest rate is not the same as APR. APR can incorporate certain fees and is often the better figure for comparing offers, so confirm which one your lender quoted.
- Secured loans (backed by a car, home, or savings) usually carry lower rates but put the collateral at risk; unsecured loans cost more but risk no specific asset. The math here is the same, but the stakes differ.
- Compare offers using APR, not just the interest rate, so fees are reflected in the number you are weighing.
- Try shortening the term by a year or two and watch the total interest drop — often the payment rises less than you expect.
- If your loan has no prepayment penalty, even a small fixed extra payment each month can meaningfully shorten the loan; model it before committing.
Frequently asked questions
What is the difference between the interest rate and the APR?
The interest rate is the cost of borrowing the principal, expressed as a yearly percentage. The APR (annual percentage rate) can also include certain fees, such as origination charges, so it often reflects the true cost of the loan more completely. When comparing offers, the APR is usually the fairer number.
How does the loan term affect what I pay?
A longer term spreads the balance over more months, lowering each monthly payment but increasing the total interest because you are borrowing for longer. A shorter term raises the payment but reduces total interest. This calculator lets you compare terms directly with your own numbers.
How much can extra payments save me?
Because interest is charged only on the remaining balance, any extra payment reduces all future interest. A modest recurring extra payment can shorten the loan by months or years and cut total interest noticeably, with the biggest effect when you pay extra early in the loan.
What is the difference between a secured and an unsecured loan?
A secured loan is backed by collateral — a car, a home, or savings — which the lender can claim if you default, and it usually carries a lower rate. An unsecured loan has no specific collateral and typically costs more. The payment math is identical, but the risk to your assets is not.
Does this calculator work for both US and Canadian loans?
Yes. Most US and Canadian consumer installment loans use the same fixed-rate, level-payment amortization with monthly compounding, which is exactly what this calculator models. Canadian mortgages are a special case with semi-annual compounding, so for a home loan use the dedicated mortgage calculator instead.
Why does so much of my early payment go to interest?
Interest each month is charged on the outstanding balance, which is highest at the start. So early payments are mostly interest with a little principal; as the balance falls, more of each fixed payment goes to principal. This shift is why extra principal early in the loan saves the most.
Sources and review notes
Methodology last checked Jul 14, 2026. Formula implementation is covered by deterministic unit tests. No financial professional review is claimed yet.