Calculation Methodology & Data Transparency

At SmartPaisa Tools, we believe in 100% transparent math. Every formula used across our flagship tools and calculators is documented here and cross-referenced with official Indian portals.

1. Income Tax Engine (FY 2026-27)

Formulated according to official guidelines published by the Income Tax Department of India:

• New Tax Regime: ₹75,000 standard deduction for salaried individuals; Sec 87A full tax rebate up to ₹12 Lakhs taxable income; 4% Health & Education Cess.
• Old Tax Regime: ₹50,000 standard deduction; Section 80C limit (₹1,50,000); Section 80D limit (₹25,000); Metro/Non-metro HRA exemption math.
• EPF Statutory Deductions: Formulated as per EPFO statutory rules (12% of basic salary up to statutory threshold).

2. Prepay Home Loan vs Invest Engine

Calculates exact monthly EMI, prepayment tenure reduction, lost Section 24(b) Old Regime tax savings, and break-even interest rate thresholds in accordance with floating rate rules set by the Reserve Bank of India (RBI).

3. City Cost-of-Living Multipliers

Sourced relative to Tier-2 baseline (1.00x) using Numbeo Cost-of-Living Index standards: Mumbai (1.45x), Bengaluru (1.35x), Gurgaon (1.35x), Hyderabad (1.20x), Pune (1.18x), Chennai (1.15x), Kolkata (1.08x), Remote (0.90x).