Loan Calculator
Estimate monthly payments and total interest for an auto, personal, or other fixed-rate loan.
Enter your numbers
Assumes a fixed rate, monthly payments, and no extra fees.
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Monthly payment
$0.00
- Principal $0
- Interest $0
Year-by-year amortization schedule
| Year | Interest | Principal | Ending balance |
|---|
Compare two scenarios
Same loan amount as above, two rate/term combos side by side.
Scenario A
Scenario B
| Scenario A | Scenario B | B − A | |
|---|---|---|---|
| Monthly payment | — | — | — |
| Total interest | — | — | — |
| Total of payments | — | — | — |
How it works
This is an amortizing loan: every month you pay the same amount, split between interest on the remaining balance and principal. The monthly payment comes from the standard loan formula:
Where P is the loan amount, r is the monthly rate (annual rate ÷ 12), and n is the total number of monthly payments. Total interest is simply all payments added up, minus the original loan amount.
The true cost of borrowing
The monthly payment is only half the story. Take a $25,000 loan at 8% for 5 years: the payment is $506.91 a month, but across 60 payments you pay $5,414.59 in interest — about 21.7% of the loan amount on top of the principal. That interest is the price of the money itself, and it is set by three levers: the rate, the amount, and the term. Shorten any one of them and the total interest falls; lengthen the term and it rises fast, because you pay interest on a high balance for longer. The donut chart above makes the split visible: the smaller the amber slice, the cheaper the loan.
Prepaying: small extras, big savings
Extra payments go straight to principal, shrinking the balance that next month's interest is charged on — and the effect compounds. On that same $25,000 at 8% for 5 years, adding just $50 a month to the $506.91 payment finishes the loan in 54 months instead of 60 and cuts total interest from $5,414.59 to $4,807.73 — a saving of about $607 for $50 a month. Two warnings: confirm there is no prepayment penalty, and tell your lender the extra is meant for principal (some apply it to future interest first, which wipes out the benefit).
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Frequently asked questions
What is the difference between APR and interest rate?
The interest rate is the cost of borrowing the principal. APR (annual percentage rate) rolls in certain lender fees and is expressed as a yearly rate, so it is usually slightly higher. Comparing APRs is the fairest way to compare loan offers.
Does a down payment change the monthly payment much?
Yes. A down payment reduces the amount you borrow, which lowers both the monthly payment and the total interest. It also reduces the risk of owing more than the asset is worth.
Should I pick a shorter loan term?
Shorter terms mean higher monthly payments but much less total interest, and often a lower rate. Longer terms keep payments affordable but cost significantly more over time. Choose the shortest term whose payment fits your budget comfortably.
Are there fees this calculator does not include?
Yes. Origination fees, late fees, prepayment penalties, and add-on products like extended warranties are not included. Always read the loan agreement so the quoted monthly payment matches what you will actually pay.