What is a Loan Calculator?
A loan calculator estimates what a fixed-rate loan will actually cost you. From three inputs — the amount borrowed (the principal), the annual interest rate, and the term in years — it derives the monthly payment, the total amount you will repay, and the total interest you will pay on top of the principal. This turns a vague idea (“I want to borrow €20,000”) into concrete numbers you can budget around before signing anything.
A fixed-rate loan works on the principle of amortization: the lender splits the debt into equal monthly payments so that the balance reaches exactly zero on the final payment date. Each payment is part interest and part principal, but the split shifts over time. Early on, most of the payment covers interest because the outstanding balance is large. As the balance shrinks, more of each payment goes to principal — which is why a loan pays down slowly at first and quickly near the end.
How to Use the Loan Calculator
- Enter the loan amount — the total sum you intend to borrow.
- Enter the annual interest rate as a percentage, exactly as the lender quotes it.
- Enter the term in years — the period over which the loan is repaid.
- Read the monthly payment: this is what leaves your account each month.
- Check the total interest to see the true cost of borrowing, and review the yearly amortization schedule.
Reading the Amortization Schedule
The amortization table groups payments by year so you can see how the loan unwinds over time. For each year it shows the principal paid down, the interest charged, and the remaining balance. Two patterns stand out. First, the interest column starts high and falls every year — proof that interest is charged only on the balance still owed. Second, the balance drops slowly in the early years; on a 25-year mortgage you may still owe more than 80% of the original amount after five years. Understanding this helps you judge whether overpaying early, or choosing a shorter term, is worth it.
A common surprise is how much a small rate change costs. On a long-term loan, even one percentage point can add thousands in total interest, because that extra rate is applied to the balance every month for the whole term. The calculator makes this visible: change the rate and watch the total interest figure move. Use it to compare offers, test the effect of a larger deposit, or see how a shorter term raises the monthly payment but cuts the lifetime cost.
Frequently Asked Questions
Is the calculated payment exact?
It is an accurate estimate for a standard fixed-rate, fully amortizing loan. Real offers may add fees, insurance, or rounding rules, so treat the result as a close planning figure rather than a binding quote.
Why is total interest so much higher than I expected?
Interest accrues every month on the outstanding balance. Over a long term those small monthly charges add up. A longer term lowers the monthly payment but increases total interest; a shorter term does the opposite.
Does this account for extra payments?
The schedule assumes the standard monthly payment with no overpayments. Paying extra reduces the principal faster and cuts total interest, but that scenario is not modelled here.
Is my financial data sent anywhere?
No. All calculations run inside your browser. The amounts and rates you enter are not transmitted to any server or stored after you close the page.