Assumptions. New regime: ₹75,000 standard deduction for salaried/pension income, slabs of ₹4L bands at 0/5/10/15/20/25/30%, Section 87A rebate nils out tax fully for taxable income up to ₹12,00,000. Old regime: ₹50,000 standard deduction, slabs of ₹2.5L/5L/10L (higher exemption for senior/super-senior), 87A rebate up to taxable income ₹5,00,000. Surcharge (10%/15%/25%, capped at 25% under the new regime) and 4% health & education cess are applied where applicable; marginal relief on surcharge and on income just above the rebate threshold is not modelled — treat results near those thresholds as indicative. This tool does not replace a proper computation for filing.