Formula Library
Savings & Interest Formulas
Google Sheets formulas for compound interest calculations, savings goal projections, and emergency fund planning.
Coast FIRE Calculator
intermediateCalculate when you can stop actively saving for retirement and let compound growth do the rest in Google Sheets.
=retirement_target / (1 + return_rate)^years_until_retirement Compound Interest (FV)
beginnerCalculate how much your savings will grow over time with compound interest using the FV function in Google Sheets.
=FV(rate/12, periods, -monthly_contribution, -initial_deposit) Compound Monthly Savings Growth
intermediateProject how regular monthly contributions grow over time using the FV function with compound interest.
=FV(annual_rate/12, months, -monthly_contribution, -starting_balance) Emergency Fund Target
beginnerCalculate your ideal emergency fund size based on monthly expenses and risk factors using a Google Sheets formula.
=monthly_expenses * months_coverage How Much Do I Need to Retire
beginnerCalculate your retirement savings target based on expected annual expenses and the 25x rule in Google Sheets.
=annual_expenses * 25 Inflation-Adjusted Value
intermediateCalculate the real purchasing power of future money by accounting for inflation using simple Google Sheets formulas.
=future_value / (1 + inflation_rate)^years Required Monthly Savings
beginnerCalculate how much you need to save each month to reach a financial goal by a target date using Google Sheets formulas.
=PMT(rate/12, months, -current_savings, goal) Rule of 72
beginnerQuickly estimate how long it takes for an investment to double at a given interest rate using this simple formula.
=72/annual_rate Safe Withdrawal Rate (4% Rule)
beginnerCalculate how much you can withdraw annually from your retirement portfolio without running out of money.
=portfolio_value * 0.04 Savings Goal Timeline
intermediateCalculate how many months it will take to reach a savings goal with regular contributions using Google Sheets formulas.
=NPER(rate/12, -monthly_savings, current_savings, -goal_amount)