calculate the maturity amount and interest earned on the basis of your monthly deposit. The RD helps you to invest a fixed amount every month, to achieve a lump sum amount along with the interest earned at the end of the tenure.
The annual interest rate, often called an annual percentage rate (APR) and it is change frequently.
It is the total amount that you will get after your time period.
Generally, minimum time period is 6 months and its usually multiple of 3.