Loan & Mortgage Calculator
🔒 Runs in your browser
For information only — not financial advice.
Monthly payment
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Total paid
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Total interest
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Amortization schedule
| Month | Payment | Principal | Interest | Balance |
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How the loan payment is calculated
Enter the amount you borrow, the nominal annual interest rate and the term, and the calculator
derives the monthly payment from the standard annuity formula: payment = P × r ÷ (1 −
(1 + r)−n), where P is the principal, r the monthly
rate (annual rate ÷ 12) and n the number of months. Every figure — the instalment,
the totals and the full month-by-month amortization table — is computed instantly in your
browser as you type.
Annuity versus equal-principal
With an annuity the total instalment is the same every month; early payments are mostly interest and the balance shifts toward principal over time. With equal principal you repay a fixed slice of the loan each month, so the instalment starts higher and falls as the outstanding balance shrinks — you pay less interest in total, but the early payments are heavier. Switch between the two schemes to compare the amortization schedule side by side.
Interest rate versus APR
The number you enter here is the nominal interest rate, which drives the interest maths. The APR (annual percentage rate) additionally includes fees such as analysis, administration and mandatory insurance, so it is usually higher than the headline rate. When comparing offers from different lenders, always compare by APR rather than by the advertised interest rate, and remember that variable-rate loans reprice as their reference index moves.
Frequently asked questions
How is the monthly payment calculated?
For an annuity loan the instalment is constant: payment = P × r ÷ (1 − (1 + r)^−n), where P is the principal, r the monthly rate (annual rate ÷ 12) and n the number of months. For 100000 at 6% over 60 months that is 1933.28 per month.
What is the difference between annuity and equal-principal repayment?
With an annuity the total instalment stays the same every month while the split shifts from interest toward principal. With equal-principal you repay a fixed slice of the principal each month, so the instalment starts higher and shrinks over time — you pay less interest overall.
What is APR versus the nominal interest rate?
The nominal rate drives the interest maths shown here. The APR (annual percentage rate) also folds in fees such as analysis, insurance and administration costs, so it is usually higher — always compare offers by APR, not the headline rate.
Is the calculation sent to a server?
No — the payment, totals and the entire amortization schedule are computed instantly in your browser; nothing is transmitted or stored.