Savings Calculator — Calculations & Slabs for FY 2026-27

Investing a lump sum of money provides a solid base, but consistently adding monthly contributions is what truly accelerates your future capital growth. This mathematical compounding synergy is the foundation of long-term financial planning.

Mathematical Equations of Savings Accumulation

The calculation combines two different formulas: the standard compound interest formula for the initial deposit and the future value of an ordinary annuity formula for the regular monthly contributions.

• Initial Deposit Growth: Calculates how the initial lump sum grows over time: FV_principal = P × (1 + r / n)^(n × t) where P is the initial deposit, r is the annual interest rate, n is the compounding frequency per year, and t is the time in years.
• Annuity Growth (Regular Contributions): Calculates how the monthly additions grow when compounded at the chosen frequency: FV_annuity = PMT × [((1 + r / n)^(n × t) - 1) / (r / n)] × (1 + r/n)^(n / 12 - 1) or approximated through monthly increments. If compounding is monthly, this reduces to: FV_annuity = PMT × [((1 + r/12)^(12 × t) - 1) / (r/12)] where PMT is the monthly contribution.
• Total Future Balance: The sum of both parts: Total Projected Value = FV_principal + FV_annuity

How Compounding Frequency Impacts Your Return

Compounding frequency is the number of times per year interest is calculated and added back to your balance. The more frequently interest compounds, the faster your savings grow:

• Monthly Compounding: Interest is calculated 12 times a year, meaning you earn interest on your interest sooner.
• Quarterly Compounding: Interest is calculated 4 times a year.
• Annual Compounding: Interest is calculated once at the end of each year.