How the PPF Calculator Works
AnyTool PPF Calculator projects a Public Provident Fund account in the browser. PPF interest is compounded annually, so for a constant yearly deposit the maturity is the future value of an annuity-due, M = A × [((1 + i)ⁿ − 1) ÷ i] × (1 + i), where A is the yearly deposit, i is the annual rate as a decimal and n is the number of years, with each deposit placed at the start of the year so it earns a full year of interest. Rather than only evaluate the closed form, the calculator builds the schedule one year at a time — adding the deposit to the opening balance, crediting a year of interest and carrying the closing balance forward — so a 5-year extension block, with or without fresh deposits, still computes correctly. The default rate is 7.1% (the current government rate) but is fully editable, and the 0% case degrades cleanly to simply the money deposited. All arithmetic is pure client-side JavaScript in a reusable PPF engine.
- M = A × [((1 + i)ⁿ − 1) ÷ i] × (1 + i); interest compounded annually
- Deposit placed at the start of each year (annuity-due / deposit-at-start)
- Schedule built year by year so extensions with or without deposits work
- Editable rate (7.1% default); 0% rate returns just the money deposited
- All math is client-side JavaScript in a reusable engine — no server round-trip
