Fixed deposits trade return for certainty. These guides give the maturity value and interest earned for each deposit size and tenure at current rates, plus how TDS and the tax on interest change what you actually keep.
How to use these guides
Match the guide to both your deposit and the term you can genuinely leave untouched, because breaking an FD early costs a penalty and the lower rate for the period you actually held it. Read the post-tax figure rather than the headline maturity value: interest is taxed at your slab, and TDS applies once it crosses the annual threshold.
Where the money is needed within a year, compare against a sweep account or a short-term debt fund before committing.