An FD is an instrument provided by banks & financial institutions where you can deposit a lump sum for a predetermined period at a predetermined rate.
RDs involve regular, fixed deposits into a financial institution over a pre-defined period for a fixed-interest investment that matures in 6 months to 10 years.
The FD interest rate is 4-8%, and the RD interest rate ranges from 5.45-7.25%.
For preserving and growing a lump sum, opt for an FD. RD in contrast, is a gradual investment scheme, allowing incremental investments for substantial long-term accumulation.