APR Calculator

This calculator estimates the nominal annual percentage rate for a regular fixed-rate installment loan with one advance and equal monthly payments.

The scheduled payment is calculated from the full principal and note interest rate. Entered prepaid finance charges are then subtracted from principal to form the modelled amount financed.

The calculator solves for the monthly rate that makes the present value of the scheduled payments equal that smaller amount financed, then multiplies the monthly rate by 12 to produce the estimated APR.

A higher entered prepaid charge generally raises the estimated APR because the borrower receives less modelled credit while making the same payment stream.

Enter the loan principal, nominal annual note rate, loan term, and prepaid finance charges you intentionally want included.

The term can be entered in years, including values such as 5.5 years, as long as it converts to a whole number of monthly payments.

Review the estimated APR, monthly payment, amount financed, finance charge, total payments, and the difference between the note rate and APR.

Open the detailed breakdown to compare principal with amount financed and scheduled interest with total finance charge.

The note interest rate determines the scheduled principal-and-interest payment on the stated loan balance.

APR is a broader borrowing-cost measure because it relates the amount and timing of credit received to the amount and timing of payments, including qualifying charges reflected in amount financed.

A loan can therefore keep the same monthly payment while showing a higher APR when prepaid finance charges reduce the amount financed.

The regulatory terminology in this page follows U.S. Regulation Z. Charge treatment can differ by transaction and jurisdiction.

The calculator assumes entered prepaid charges reduce the credit represented by the transaction rather than increasing the principal balance.

Payments are still calculated from the full principal. APR is solved against the smaller amount financed.

Receiving less net credit while making the same scheduled payments increases the rate implied by the payment stream.

Principal is the balance used to calculate the scheduled payment.

Amount financed is principal minus the entered prepaid finance charges under this calculator's assumptions.

For a $200,000 principal with $4,000 of entered prepaid charges, amount financed is $196,000 while the payment remains based on $200,000.

Not every closing or origination cost is necessarily a finance charge for an official APR calculation.

Treatment can depend on the type of credit, the specific charge, who requires it, and applicable rules.

Use the lender's official disclosures or qualified professional guidance when deciding which charges legally belong in APR.

The calculator first computes the regular monthly payment from principal, note rate, and the number of payments.

It then finds the monthly actuarial rate that makes the present value of those payments equal amount financed.

Because the rate is implicit in the present-value equation, the calculator uses an iterative numerical search.

For monthly payment periods, the estimated APR is the nominal annual rate: the solved monthly rate multiplied by 12. It is not the effective annual yield produced by compounding that rate for 12 months.

Scheduled interest equals total scheduled payments minus principal.

Finance charge in this model equals total scheduled payments minus amount financed.

Because amount financed is principal minus entered prepaid charges, finance charge equals scheduled interest plus those charges.

APR is most useful when comparing loans with similar principal, term, payment structure, and purpose.

Compare APR alongside monthly payment, upfront cash, note rate, total payments, prepayment terms, and the expected time you will keep the loan.

A borrower who refinances or repays early can experience upfront charges differently because those costs are spread across fewer months.

Official calculations can depend on exact dates, irregular periods, payment rounding, financed charges, regulatory treatment of individual costs, and the actual contractual payment schedule.

This calculator assumes one advance followed by equal end-of-month payments beginning one month later.

It is suitable for education and initial comparison, not lender-disclosure or regulatory-compliance testing.

The calculation, cost comparison, print output, and CSV report are generated locally in the browser.

The current loan inputs are saved in browser local storage so they can reappear on the same device. Reset replaces them with the default values rather than deleting the storage keys.

The interface can read valid assumptions supplied through existing URL parameters, but it does not generate a new public sharing link.

The result is not a loan offer, official disclosure, appraisal, underwriting decision, or legal determination of finance charges.