Loan Interest Calculator
Monthly payment and total interest for equal-payment, equal-principal or interest-only loans.
About this tool
Enter the amount, the annual interest rate and the term, and this tool works out what you pay each month and what the interest adds up to over the life of the loan. The repayment schedule breaks every instalment down into principal, interest and the balance remaining.
There are three repayment methods. Equal payment — the most common — charges the same amount every month; early on most of it is interest, and the share going to principal grows over time. Equal principal divides the principal evenly across the term, so the first instalment is the heaviest but the total interest is the lowest of the three. Bullet repayment charges interest only each month and the whole principal at maturity, which is the lightest monthly burden and the most expensive overall.
Because the total interest differs sharply between the three for otherwise identical terms, it is worth switching between them to compare. Note that this is a plain calculation: early repayment fees, arrangement fees and grace periods are not included, and real loans carry those and may have variable rates. Confirm the final terms with the lender.