Fixed Deposit (FD) Calculator

The formula

Maturity = P × (1 + r/400)^(4t)

Quarterly compounding divides the annual rate by 400 (4 periods × 100), and the exponent counts quarters. At 7.5% the quarterly rate is 1.875%, and twelve quarters multiply the principal by 1.2497.

TDS is charged on the interest, not the maturity value: 10% of ₹24,971.64, not 10% of ₹1,24,971.64. That distinction changes the answer by an order of magnitude and is the most common error in hand calculations.

Worked examples

₹1,00,000, 7.5%, 3y → ₹1,24,971.64, ₹1,22,474.47 after TDS
₹50,000 → ₹62,485.82, ₹61,237.24 after TDS
₹2,00,000 → ₹2,49,943.28, ₹2,44,948.95 after TDS
3.75% instead of 7.5% → ₹1,11,848.59
15% instead of 7.5% → ₹1,55,545.43
1.5 years → ₹1,11,790.71
6 years → ₹1,56,179.10
5% TDS → ₹1,23,723.06

Doubling the principal doubles every line — the deposit is linear in amount. Doubling the rate does not double the interest, because compounding works on a larger base each quarter: 15% adds ₹30,574 over three years while 7.5% adds ₹24,972, a 22% increase in interest rather than 100%.

Where the money actually goes

Banks deduct TDS at 10% when interest in a financial year exceeds ₹40,000 for a regular depositor (₹50,000 for seniors). If your total income is below the taxable threshold, the deduction can be avoided by submitting Form 15G or 15H — otherwise the tax is withheld and reclaimed only through a return.

The effective yield is what matters for comparison. This deposit pays 7.5% nominal, but after 10% TDS on the interest the annualised return is closer to 7.1%, and after income tax at the depositor’s slab it can fall below inflation. A tax-free instrument at 6.5% can beat this one for someone in the 30% bracket.

Premature withdrawal usually costs 0.5–1% of the rate, and the penalty applies to the whole term, not just the remaining period. If the money might be needed early, a shorter tenure or a ladder of deposits avoids the hit.

Renewal is a separate decision. When the term ends, the bank rolls the deposit into a new one at whatever rate is on offer that week, often a default rate below the card rate. Diarise the maturity date and give the branch instructions in advance rather than letting it auto-renew, because a single renewal at the wrong rate can cost more than the TDS on the whole deposit. Splitting a large sum into three deposits of different tenures — a ladder — also keeps one tranche maturing each year, so a rate rise can be captured without breaking anything.

Frequently Asked Questions