PPF or NPS for the next 15 years

PPF is EEE, capped at 1.5 lakh a year, 15-year lock, rate reset by the government. NPS is the engine: equity up to 75% when young, an extra deduction under 80CCD(1B), and a forced annuity of at least 40% at 60.

If you can only fund one, fund PPF first up to the cap. Then NPS.

Run both calculators with the same monthly amount and compare.