Step 1 - Choose your starting date.

Select the starting date of your choice using the drop-down arrows next to each selection box. The day of the week will be calculated automatically for you. When you first open the Interest Calculator, the date is automatically set to today's date. As the calculator takes today's date from your system clock, it is important to make sure that your system date is correctly set for this function to work properly.

Step 2 - Choose your ending date.

Select the ending date of your choice using the drop-down arrows next to each selection box. The day of the week will be calculated automatically for you. When you first open the Interest Calculator, the date is automatically set to today's date. As the calculator takes today's date from your system clock, it is important to make sure that your system date is correctly set for this function to work properly.

Step 3 - Enter your principal sum.

Enter the principal sum on which you want interest to be calculated. You should not enter any currency sign. Nor should you enter any commas in the number.

Step 4 - Enter your rate of interest.

Enter the annual rate of interest which you wish to apply to your principal sum. You should not enter any percentage sign. Nor should you enter any commas in the number.

Step 5 - Calculate.

Press the button marked "Calculate" to carry out the calculation. On the right hand side of the form will be displayed the number of days difference between your starting date and your ending date, the interest on the principal sum (rounded to two decimal places), and the total of the principal sum plus the interest (again rounded to two decimal places).

Method of calculation:
The interest is calculated as simple interest using the conventional approach used by litigation lawyers in England and Wales. This approach is to calculate the annual amount of interest on the principal sum, then divide by 365 to obtain a daily amount of interest, and then multiply this daily amount by the actual number of days in the relevant period. Note that the calculation excludes the starting date itself (ie. day number 1 is the day after your starting date) but includes the ending date.

Year 2000 compliance:
This calculator is year 2000 compliant, assuming that the system on which it is used is also year 2000 compliant. In other words, it works for dates before, after, in, and spanning, the year 2000.

Browser compatibility:
This calculator is designed for use with Microsoft Internet Explorer version 5.0 and above, or Netscape Navigator version 4.06 and above. This page is best viewed at a resolution of 800 x 600 or higher.