Personal Loan Calculator: Monthly Payment & Total Interest
Enter the amount, APR, and term to see your monthly payment, the total interest, and what you'll repay in all. The year-by-year table shows how the balance falls as payments shift from interest to principal.
What you'd borrow, before any origination fee
The annual rate on your offer, fees included
Loan term (months)
Any length your lender offers
Monthly payment
$399
on $15,000 at 12.5% for 4 years
Total interest
$4,138
the cost of borrowing, on top of the principal
Total repaid
$19,138
48 payments of $399
Year-by-year balance
| Year | Principal paid | Interest paid | Remaining balance |
|---|---|---|---|
| 1 | $3,082 | $1,702 | $11,918 |
| 2 | $3,490 | $1,294 | $8,428 |
| 3 | $3,952 | $832 | $4,476 |
| 4 | $4,476 | $309 | $0 |
Early payments are interest-heavy; the balance falls faster near the end. Extra principal payments shorten the schedule from the back.
The amortization math behind the payment
A personal loan uses the standard amortization formula: payment equals principal times the monthly rate, divided by one minus (1 + monthly rate) raised to the negative number of months. Each payment first covers the interest the balance earned that month, and whatever remains retires principal. Because the balance shrinks every month, the interest share shrinks with it, which is why the year-by-year table shows principal accelerating toward the end. A worked example: $15,000 at 12.5% APR over 48 months prices out at about $399 a month. Over four years that is roughly $19,100 repaid, of which about $4,100 is interest. Stretch the same loan to 60 months and the payment drops to about $337, but the interest bill grows past $5,200.
APR is not the interest rate, and the gap is the fees
Lenders quote two numbers. The interest rate prices the borrowed money itself; the APR adds required fees, most commonly an origination fee of roughly 1-10% that is deducted from your proceeds before the money arrives. That makes APR the honest cost of the loan and the only number worth comparing across offers. This calculator asks for APR, so fees are already baked into the payment it shows.
What actually moves personal loan rates
Most personal loans are unsecured debt: no collateral backs them, so pricing leans almost entirely on your credit profile. Credit score does the heavy lifting, followed by your debt-to-income ratio, income stability, and the loan's size and term. Shorter terms typically price lower than longer ones because the lender's risk window is smaller. Broad rate conditions matter too: personal loan APRs tend to track the general level of interest rates, so the same borrower can see different offers a year apart.
When this calculator earns its keep
Run it before you apply, not after. Knowing that a $15,000 loan costs about $399 a month at 12.5% tells you instantly whether an offer at 15.9% is worth walking away from, and what a longer term really buys. It is also the first step in a consolidation decision: the debt consolidation calculator compares a loan like this against the debts it would replace, so you can see whether borrowing at your offered rate beats simply paying down what you already owe.
Frequently asked questions
How is a personal loan payment calculated?
By standard amortization: the loan amount, the monthly rate (APR divided by 12), and the number of months set a fixed payment that covers that month's interest first and principal second. Borrowing $15,000 at 12.5% APR for 48 months comes to about $399 a month, roughly $4,100 of which is interest over the life of the loan.
What is the difference between APR and interest rate?
The interest rate is what the lender charges on the balance. APR folds required fees, most often an origination fee, into that rate, so it reflects the true annual cost of the loan. Two offers with the same interest rate can have very different APRs, which is why APR is the number to compare.
What is a typical APR on a personal loan?
It varies widely with credit. Borrowers with excellent credit often see rates in the high single digits to low teens, average credit tends to land in the mid-teens to low twenties, and weaker credit can reach 30% or more. Personal loans are usually unsecured, so your credit profile does most of the pricing work.
Do personal loans have origination fees?
Many do, typically around 1-10% of the loan amount, and the fee is usually deducted from the money you receive. If you need $15,000 in hand and the fee is 5%, you would have to borrow closer to $15,800. The APR on your offer already includes this fee, which is another reason to compare APRs rather than rates.
Is a shorter or longer term better?
A shorter term costs less in total because interest has less time to accrue, but the monthly payment is higher. A longer term buys a smaller payment with more total interest. The table in the calculator makes the trade visible: many people pick the shortest term whose payment still fits comfortably in their budget.
Does this calculator save my numbers?
No. Everything runs in your browser and nothing you type is stored or sent anywhere.
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