What Will That Loan Really Cost?
Every loan is three numbers — amount, interest rate, term — but the number that matters to your life is a fourth: the monthly payment, and behind it, the total interest you will hand over before the debt dies. This calculator turns the three inputs into the full picture instantly: the fixed monthly installment (the “EMI”), the total amount you will repay, the total interest within it, and a year-by-year amortization view showing how each payment splits between interest and principal. Whether you are sizing a mortgage, comparing car financing offers, or sanity-checking a personal loan, the arithmetic here is the standard formula every bank uses.
How to Use It
- Enter the loan amount (the principal you would borrow).
- Enter the annual interest rate as quoted — the calculator converts to monthly internally.
- Set the term in years or months.
- Read the monthly payment, total repayment and total interest; expand the amortization table to see the balance shrinking year by year.
The Formula, in Daylight
The fixed payment comes from the standard annuity formula: EMI = P × r × (1+r)ⁿ ÷ ((1+r)ⁿ − 1), where P is principal, r the monthly rate (annual ÷ 12) and n the number of months. Its character is worth understanding: early payments are mostly interest, because interest accrues on the still-large balance; only over time does the principal share grow. That is why early extra payments are disproportionately powerful — money paid against principal in year two saves more interest than the same money in year twelve — and why the amortization view is the most educational part of this page.
What to Compare When Comparing Loans
- Total interest, not just the monthly payment. Stretching a term shrinks the installment but inflates the total cost — visible here side by side by running both scenarios.
- The rate type: this calculator models a fixed rate. Variable-rate loans recalculate when rates move; treat results as a snapshot at today's rate.
- The fees outside the rate: origination charges, insurance and mandatory extras are not in the interest rate, which is why regulators publish APR-style total-cost measures. Compare offers on total cost, not the headline rate.
- Rounding conventions: banks round payments their own ways, so expect agreement to within a small amount per installment, not to the cent across decades.
An Honest Boundary
This is an information tool, not financial advice. It computes the standard formula exactly and runs entirely in your browser — your financial inputs are never transmitted anywhere, which matters for numbers this personal. But a real borrowing decision involves your income stability, local regulations, tax treatment and the fine print of a specific contract, and that synthesis is a job for a qualified human advisor with the actual documents in hand. Use this page to understand the mechanics, narrow your options and walk into that conversation knowing what the numbers mean — that is precisely what it is for.
The most valuable five minutes you can spend here is scenario comparison: run your loan at the offered rate, then at half a point lower, then with a 10 percent larger down payment, and watch the total-interest figure respond. Those three numbers — more than any sales conversation — show you exactly what negotiating the rate or saving a little longer is actually worth in your own currency.
Frequently Asked Questions
Why is most of my early payment interest?
Interest accrues on the outstanding balance, which is largest at the start. As payments shrink the principal, the interest share falls and the principal share grows — the amortization table shows the crossover.
Does a longer term make a loan cheaper?
It lowers the monthly payment but raises the total interest, often dramatically. Run both terms here and compare the “total interest” figures — that one number usually settles the question.
Why does my bank’s quoted payment differ slightly?
Rounding conventions, fee handling and day-count methods vary between lenders. Expect agreement within a small amount per installment; large gaps usually mean fees are embedded that the headline rate omits.
Are my loan details sent anywhere when I calculate?
No. The formula runs locally in your browser and nothing you enter is transmitted or stored — appropriate for numbers as personal as your debts.