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Loan Calculator

Find the monthly payment, total interest and true cost of a loan or mortgage. Adjust the amount, rate or term and everything recalculates instantly.

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Assumptions. A fixed-rate, fully-amortising loan with equal monthly payments — the standard structure for mortgages and personal loans. It excludes fees, insurance, taxes and any variable-rate changes, which your lender's offer will set out.

A loan is one line on your balance sheet.

Manticore Finance tracks your debts next to your assets, so you see net worth — not just what you own, but what you owe against it, and how that changes over time.

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How a loan payment is calculated

With a fixed-rate amortising loan, every monthly payment is the same, but its split shifts over time: early on, most of it is interest and only a little pays down the balance; later, as the balance shrinks, more of each payment is principal. The fixed payment is set so the loan reaches exactly zero at the end of the term.

The formula is M = P · i / (1 − (1 + i)−N), where P is the amount borrowed, i is the monthly rate (annual ÷ 12) and N is the number of monthly payments.

How to use it

Enter the amount, the rate you've been quoted, and the term. Watch the total interest as you change the term: a shorter term means a higher monthly payment but far less interest over the life of the loan, because the balance is cleared sooner.