Loan repayment calculator
Calculate your monthly payment, total interest, and full amortization schedule for personal installment loans. Use this to estimate cost before you apply or to verify the numbers in a loan offer you've already received.
How is loan repayment calculated?
A personal loan repayment calculator computes your monthly payment using the standard amortization formula based on loan amount, APR, and term length. For a $2,000 loan at 35.99% APR over 12 months, the monthly payment is approximately $200, total interest is around $400, and total repayment is $2,400. Adjust the inputs to see how each variable affects total cost.
How to use this calculator
Adjust the three inputs at the top — loan amount, APR, and term — and the monthly payment, total interest, and total repayment update immediately. The bar below shows what portion of your total payment goes to principal versus interest, and the amortization schedule (when you expand it) shows the exact split for every payment.
What changes the monthly payment most
Three variables drive the math:
- Loan amount. Doubling the principal roughly doubles the monthly payment, all else equal.
- APR. Higher APR means more of each payment goes to interest, increasing both monthly payment and total cost.
- Term length. Longer terms reduce the monthly payment but increase total interest because you're paying interest for more months.
The third one trips people up most. A 24-month term feels easier than a 12-month term because the monthly payment is smaller, but the total cost is higher — sometimes substantially. For a $2,000 loan at 36% APR, the 12-month total cost is around $2,400, while the 24-month total cost is around $2,800. You're paying $400 more for the privilege of stretching the payment.
What this calculator doesn't include
Important caveats before you use these numbers for real planning:
- Origination fees. Most subprime lenders charge a 1-10% origination fee that's deducted from your loan proceeds. This makes the true APR higher than the stated interest rate. See our APR calculator for the corrected number.
- Late fees and NSF fees. Optional fees that depend on borrower behavior aren't part of the APR calculation. Plan for $15-$30 per late payment in most states.
- State-specific rules. Some states cap APRs (Illinois, Virginia, Ohio, etc.). The calculator doesn't validate against state rules — check our state pages for specific restrictions.
This calculator is meant to give you a clean estimate of the basic loan math. For comparing real loan offers, the lender's federal Truth-in-Lending disclosure (the TILA box) is what to look at — it includes APR, finance charge, and total of payments, all required by federal law.
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Frequently asked questions
How is the monthly payment calculated?
The calculator uses the standard amortization formula for fixed-rate installment loans: P × [r(1+r)^n] / [(1+r)^n - 1], where P is the loan amount, r is the monthly interest rate (APR ÷ 12), and n is the number of payments. This is the same formula your lender uses to set your scheduled payment.
Why does my actual loan offer show a different monthly payment?
Most subprime online loans include an origination fee that's deducted from your loan proceeds at signing. This fee makes the true APR higher than the stated interest rate. The difference between this calculator and an actual offer usually comes down to fees not included here. Use the APR calculator if you want to see how fees change the picture.
How much of my payment goes to principal vs interest?
On a fixed-rate amortizing loan, early payments are mostly interest and late payments are mostly principal. The amortization schedule shows the exact split for every payment. Loans with higher APRs have more interest-heavy front-loading; loans with lower APRs flip to principal-heavy faster.
Will paying early reduce the total interest?
Yes, in most cases. Personal installment loans typically allow early payoff without penalty, and paying early reduces the outstanding principal balance, which reduces future interest charges. Some states require lenders to refund unearned interest on early payoff. Check your loan agreement before making extra payments.
What APR should I use for my estimate?
For subprime online installment loans, APRs commonly run 35-200% depending on credit profile, loan amount, and state. For fair credit, expect 25-50%. For good credit, expect 10-25%. The calculator default of 35.99% reflects a typical subprime offer in a state without low rate caps. Use the APR you've actually been quoted for accurate planning.
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