How this calculation works
Begin from zero and add the same annual sum to both scenarios. PPF interest uses the modeled eligible monthly balances and annual credit. The FD side assumes each annual contribution and renewed balance compound monthly for a complete year. The effective annual rate calculator helps distinguish nominal and effective rate inputs.
PPF year interest = opening × p + annual deposit × p × eligible months /12; FD grows monthlyA worked example
For a one-year ₹1,00,000 contribution by 5 April, a hypothetical 7% PPF rate produces ₹1,07,000. A zero-rate FD scenario stays at ₹1,00,000, so the pretax modeled difference is ₹7,000.
Good to know
Both rates are entered constant assumptions, not quoted or guaranteed future rates. Complete financial years only; the projection is not a legal maturity-date calculation. Internal annual balances stay unrounded, so actual posting can differ. No tax, deduction value, partial opening year, withdrawal, loan, renewal-rate change or liquidity comparison.
Reference: National Savings Institute: PPF Scheme 2019, as amended (opens in a new tab) ↗
Use equal funding before comparing balances
A lump-sum FD and a PPF account with annual deposits do not have the same cash flow. This model starts both balances at zero and contributes the same entered amount once in every complete modeled financial year.
The FD side assumes start-of-year funding and monthly compounding, with renewed balances staying at the same assumed rate. This describes a hypothetical deposit portfolio; it is not a quote for one fixed-deposit contract with future top-ups.
The step-up SIP calculator changes monthly funding each year. This PPF vs FD contribution calculator instead compares equal annual funding and explicit interest conventions.
The April timing choice changes eligible PPF months
The PPF model uses the eligible monthly balance convention around the close of the fifth day. A contribution by the close of 5 April participates for twelve modeled months; a contribution later in April participates for eleven. The opening balance participates throughout the year.
At an assumed 7% rate and a ₹1,00,000 first-year deposit, the early-April interest is ₹7,000. The later-April arithmetic gives ₹6,416.67 before account-posting rounding. Future interest is credited annually in this projection, not monthly.
A pretax balance difference is one limited comparison
Both rates stay constant only to isolate the modeled cash flows. Actual PPF rates can change, FD renewal rates can change, and tax treatment, liquidity and account rules can affect a real decision. This page does not rank products or assign a value to those differences.
The effective annual rate calculator checks the FD compounding convention. A step-up SIP calculator models a different contribution pattern and return assumption. This PPF/FD page uses complete years and unrounded internal balances; it does not determine a legal account maturity date.
A few questions, answered
Are the entered rates current product rates?
No. They are scenario inputs held constant across the projection, with no promise that either rate is available or will persist.
Does fifteen projection years give my account’s maturity date?
No. A legal maturity date depends on actual account opening and scheme rules. This form models complete financial years only.
Does the difference include income tax or deduction benefits?
No. FD balances are shown before tax, and no value is assigned to a deduction, exemption or liquidity restriction.