Loan Calculator — Monthly Payments, Interest & Total Cost
Calculate your monthly loan repayment, total amount repaid, and total interest for any loan — personal loan, car loan, mortgage, or business loan. Enter the loan amount, interest rate, and term to get your full breakdown instantly.
Use this calculator before taking any loan to understand exactly what you will pay over the life of the loan and whether it fits your budget.
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Loan details
Enter your loan details above to see the full breakdown.
Loan breakdown
Monthly payment
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Total repayment
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Total interest paid
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Interest as % of loan
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Loan amount
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Number of payments
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How Loan Payments Are Calculated
The standard loan payment formula — used by banks and lenders worldwide — is based on the principal, interest rate, and number of payments. It produces equal monthly payments that cover both principal and interest, with the interest portion decreasing over time as the balance reduces.
Formula: M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1] Where: P = principal · r = monthly rate · n = number of months
The two most effective ways to reduce interest: (1) Choose a shorter loan term — monthly payments are higher but total interest is much lower. (2) Make extra payments towards the principal — this reduces the balance faster and saves significant interest. Even one extra payment per year can shorten a loan considerably.
Always compare the APR (Annual Percentage Rate) across lenders, not just the interest rate — APR includes fees and gives a true cost comparison.
Frequently Asked Questions
How is the monthly payment calculated?
The monthly payment uses the amortisation formula: M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1]. P is the principal (loan amount), r is the monthly interest rate (annual rate ÷ 12), and n is the number of monthly payments. Each payment covers the interest accrued that month plus a portion of the principal.
What happens if I make extra payments?
Extra payments reduce your outstanding principal faster, which reduces future interest charges. Even small additional payments can shorten your loan term significantly. Some loans have early repayment charges — check your loan agreement before making extra payments.
What is APR vs interest rate?
The interest rate is the basic cost of borrowing. APR (Annual Percentage Rate) includes the interest rate plus any fees, charges, or other costs — giving a truer picture of the total annual cost of the loan. When comparing loans, always compare APRs.
How much can I borrow?
Lenders typically assess affordability based on your income, existing debts, credit score, and the debt-to-income ratio. A common guideline is that total debt payments should not exceed 36–43% of your gross monthly income. Use this calculator to find a monthly payment that fits comfortably in your budget.