For fortnightly and weekly repayments, there are several methods to calculate repayments. Among them, two are most popular: (1) Actuarial Method which calculates the minimum repayments such that the loan can be paid off at the end of the term, not sooner and not later. It is true fortnightly and weekly repayments.
Another method is (2) Half Monthly Repayment Method which calculates fortnightly and weekly repayments simply by dividing the monthly repayment by two and four respectively.
In method two, the fortnightly or weekly repayment will be higher than the actuarial method, which in effect, results in the borrower making extra repayments over the same 12 month period. The borrowers will repay the loan sooner and also save some interest.
This calculator can help borrowers find how much interest and time can be saved if they make 1/2 or 1/4 of monthly repayments every two weeks or one week.

- It does not take into account any possible loan fees.
- Interest rate does not change over the loan term.
- Interest is calculated by compounding on the same repayment frequency selected, i.e. weekly, fortnightly, monthly. In practice, interest compounding frequency may not be the same as repayment frequency.
- It is assumed that a year consists of 26 fortnights or 52 weeks, which is counted as 364 days rather than 365 or 366 days.
- No rounding is done throughout the calculation whereas repayments are rounded to at least the nearer cent in practice.