How we calculate

Income tax

Slabs, standard deductions, the rebate (formerly Section 87A) with marginal relief, surcharge with marginal relief at each threshold, and 4% health and education cess, all for FY 2026-27. Old regime deductions are capped at their legal limits: ₹1.5 lakh for 80C, ₹1 lakh combined for 80D, ₹2 lakh for interest on a self-occupied home loan, ₹50,000 for 80CCD(1B). Employer NPS contributions reduce taxable income in both regimes; we take the figure you enter and do not check it against the percentage-of-salary cap. HRA exemption is taken as entered.

The calculator does not cover capital gains taxed at special rates, agricultural income, or business income rules. It treats all income as taxed at slab rates.

SIP and goal planning

Instalments are invested at the start of each month and compound monthly at the annual rate divided by 12. A step-up raises the instalment once every 12 months. Values are before tax and before fund expense ratios. Inflation-adjusted values divide the future amount by (1 + inflation) raised to the number of years.

FIRE

Monthly expenses are grown by inflation to the retirement year. The corpus is that year's spending divided by the withdrawal rate. Existing savings compound annually at the expected return. The required SIP closes the remaining gap using the SIP method above.

Home loan prepayment

Standard reducing-balance EMI, interest charged monthly on the outstanding balance. A monthly top-up goes entirely to principal. After a lump-sum payment, "same EMI" keeps the instalment and shortens the loan, while "same end date" recalculates the EMI over the remaining months.

Rates

Repo rate and small savings rates are taken from official announcements and linked on each page, with the date we last checked them.