All FirePlanIO Financial Calculators
Choose a tool below. Each calculator runs 100% in your browser — your inputs never leave your device — and includes an in-depth explainer of the formula behind every result. Use them to compare scenarios for growth, goals, debt freedom, early retirement, and recurring spending.
Compound Interest Calculator
Project long-term growth from a starting balance, monthly contributions, and your chosen compounding frequency.
Open calculatorSavings Goal Calculator
Work backwards from a target amount to the exact monthly deposit required within your time horizon.
Open calculatorMortgage & Loan Payoff Calculator
Compare a standard amortization schedule against extra principal payments and see the interest saved.
Open calculatorRetirement (FIRE) Calculator
Find your financial independence number and the age your portfolio can sustain your spending.
Open calculatorSubscription Cost Tracker
Add every recurring charge and see its true 10-year opportunity cost if invested instead.
Open calculator