Free Financial Calculators
These free financial calculators show how savings grow, what debt costs, where pay goes and how college aid works, and each one runs in the browser with no signup.
Compound Interest Calculator
Follows a starting amount and regular deposits as they grow, with the interest earning interest of its own.
Simple Interest Calculator
Compares interest paid on the original amount alone with interest that keeps building on itself.
What-If S&P 500 Calculator
Looks back at what a one-time or monthly investment would be worth today if it began in a past year.
Rule of 72 Calculator
Estimates how many years money takes to double at a given interest rate, and how close the shortcut is.
Dividend Calculator
Shows how dividends that buy more shares grow an investment compared with taking them as cash.
Opportunity Cost Calculator
Weighs a purchase against what the same money could grow to if it were invested instead of spent.
Credit Card Payoff Calculator
Shows how long a card balance takes to clear and what the interest costs at different monthly payments.
Sports Betting Calculator
Puts a number on the expected cost of regular bets over a season, using the house edge in the odds.
First Paycheck Calculator
Follows a first paycheck from gross pay to take-home pay, with each tax and deduction taken out in turn.
50/30/20 Budget Calculator
Splits monthly take-home pay into needs, wants and savings, and shows where rent fits inside the needs.
Tax Bracket Calculator
Walks income through each federal tax bracket to show the tax in every step and the overall rate.
FAFSA SAI & Pell Grant Estimator
Figures a family's Student Aid Index and a possible Pell Grant for a college year from a few details.
Teacher Loan Forgiveness Calculator
Weighs Teacher Loan Forgiveness against Public Service Loan Forgiveness for a teacher's federal loans.
Teacher Retirement Calculator
Estimates a teacher's monthly pension and the earliest age to retire without a reduction, state by state.
403(b) vs 457(b) Calculator
Shows how savings split between a 403(b) and a 457(b), what each plan could hold, and where the limits sit.
Summer Pay Calculator
Shows how much to set aside from each school-year paycheck so the summer months are covered.
PSLF Buyback Calculator
Estimates what buying back PSLF months could cost and how close it brings a borrower to 120 payments.
Financial calculator questions
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