Loan Calculator
Compare three repayment methods and see each payment split into principal and interest — instantly, without sending your figures anywhere.
- Fewer clicks, keyboard friendly
Change a number to update the payment estimate and repayment schedule instantly.
Saved in this browserEstimated repayment
Monthly schedule using annual rate ÷ 12. Lender rounding, fees, and daily interest rules can change the actual amount.
Repayment schedule
Each row separates the payment into principal and interest.
How to use
- Enter the amount you plan to borrow in your chosen currency.
- Enter the nominal annual interest rate and the repayment term in whole months.
- Choose Equal payment, Equal principal, or Interest-only repayment.
- Review the first payment, final payment, total interest, and total repayment as they update.
- Open the repayment schedule to inspect the principal, interest, and remaining balance for every month.
How the monthly loan payment is calculated
For an equal-payment loan, the monthly payment is P × r ÷ (1 − (1 + r)^−n), where P is the opening principal, r is the monthly rate (annual rate ÷ 12 ÷ 100), and n is the number of monthly payments. The payment stays almost constant, but its makeup changes: interest is calculated from the remaining balance, so the interest share falls and the principal share rises over time. At a 0% rate, the calculation simply divides the principal by the number of months.
Equal payment, equal principal, and interest-only repayment
Equal payment (often called amortizing repayment) makes budgeting simpler because the regular payment is level. Equal principal repays the same principal amount every month, so payments start higher and fall as interest drops; with the same positive rate and term, it produces less total interest because the balance falls faster. Interest-only repayment keeps the principal unchanged during the term, so each regular payment is interest only and the whole principal is due in the final month. At a positive rate, it produces the highest total interest of these three methods and requires planning for the final lump sum. At 0%, all three methods have zero interest.
Why your lender’s figure can differ
This calculator uses a monthly rate equal to the stated annual rate divided by 12 and does not include fees, insurance, taxes, prepayment charges, or rate changes. Lenders can instead accrue interest by actual days in a month, use 30/360 conventions, round each monthly payment to the smallest currency unit, or apply a different first-payment date. Use the schedule to compare offers, then check the lender’s disclosure and loan agreement for the contractual payment and annual percentage rate (APR).
Frequently asked questions
What is the formula for a monthly loan payment?
For a standard equal-payment loan, the monthly payment is P × r ÷ (1 − (1 + r)^−n): P is the loan amount, r is the annual rate ÷ 12 ÷ 100, and n is the number of monthly payments. A $10,000 loan at 6% for 12 months has a calculated payment of about $860.66 before lender-specific rounding or fees.
Which repayment method has the lowest total interest?
For the same principal, positive fixed rate, and term, equal-principal repayment has the lowest total interest among these three methods because it reduces the balance by the same amount from the first month. Interest-only repayment has the highest total interest because the principal remains unchanged until the final payment. At a 0% rate, all three methods have zero interest.
Does an interest-only loan pay off the principal?
An interest-only loan pays no principal during its regular interest-only period, so the original balance remains due in the final month in this calculator. For example, a $10,000 loan at 6% costs $50 in monthly interest, then requires $10,050 in the final month of a 12-month term.
Why is my lender’s monthly payment different from this estimate?
A lender may calculate interest by actual days, round each instalment, include fees or insurance, set a nonstandard first payment date, or change a variable rate. This calculator uses annual rate ÷ 12 and excludes those charges, so its result is an estimate rather than a loan offer.
Does this loan calculator store or send my financial information?
No. The calculation runs in your browser and the amount, rate, term, and selected method are saved only in this browser’s local storage for convenience; they are not sent to a server.
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Updated 2026-10-19