Loan Calculator
See what a loan will cost you per month and in total over the term, based on loan amount, nominal interest rate and number of years — or work it out the other way: how much you can borrow for a given monthly payment.
At —% interest, the monthly payment would be — — — more per month than today.
How to use the loan calculator
- Enter how much you plan to borrow.
- Enter the nominal annual interest rate — you'll find this in your loan offer.
- Enter how many years you'll pay off the loan. The calculator shows the monthly payment and total cost.
How the loan is calculated
The calculator uses the amortization formula, the most common way lenders calculate fixed monthly payments. The formula ensures you pay the same amount every month throughout the term, even though the split between interest and principal changes along the way.
where L is the loan amount, r is the monthly interest rate (annual rate ÷ 12 ÷ 100), and n is the number of months.
Worked example: a $30,000 loan at 6.5 % over 5 years gives a monthly rate of 6.5 % ÷ 12 = 0.5417 % across 60 payments, so (30,000 × 0.005417) ÷ (1 − 1.005417⁻⁶⁰) = $587 per month. You repay $35,219 in total, of which $5,219 is interest. The payment stays the same every month, but its composition shifts: in the first month 30,000 × 0.005417 = $163 goes to interest and the rest to principal, while near the end almost all of it reduces the balance.
At the start of the loan, a larger share of the payment goes toward interest, while the share going toward paying down the principal increases as the debt gets smaller.
The "How much can I borrow?" tab flips the formula around: you enter what you can afford per month, the interest rate, and the term, and the calculator works out the max loan amount — the same amortization formula, just solved for the loan amount instead of the payment.
If you enter an extra amount per month, the calculator simulates the payoff month by month with that extra amount added to every payment, and shows how much sooner the loan is paid off and how much you save in interest compared to the original term. The full amortization schedule below always reflects any extra payment you've entered.
Frequently asked questions
What's the difference between nominal and effective interest rate?
Nominal interest is the stated annual rate without fees. Effective interest also includes origination and other fees, giving a more accurate picture of the actual cost.
What's an amortizing loan?
An amortizing loan has the same total monthly payment throughout the term, but the split between interest and principal changes over time. This is the most common loan type for mortgages and personal loans.
Is it cheaper to pay off the loan faster?
Yes. A shorter term gives a higher monthly payment, but significantly lower total interest costs, since you pay interest for fewer months.
I know what I can afford per month — how much can I borrow?
Use the "How much can I borrow?" tab. Enter your desired monthly payment, interest rate and term — the calculator works out the maximum loan amount that gives exactly that payment. This is useful for setting a realistic budget before you apply for a loan.
How much do I actually save by paying a bit extra each month?
Often more than you'd think, especially early in the loan — every extra dollar goes directly toward reducing the balance, which in turn reduces the interest charged in every future month. Enter an amount in the "Extra payment per month" field to see exactly how much sooner your loan is paid off and how much interest you save.