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All calculators
22 calculators and counting.
Retirement
Retirement Calculator Enter your age, savings, and monthly contribution to see what your retirement balance could become, shown both in future dollars and in today’s purchasing power. IRA Growth Calculator See how regular IRA contributions can grow over time with monthly compounding. Mega Backdoor Roth Calculator Calculate the extra after-tax 401(k) contributions you can make and convert to Roth, on top of your normal deferral and employer match. Coast FIRE Calculator Coast FIRE is the amount invested today that grows into your full retirement target on its own, letting you stop adding new money. FIRE Number Calculator Your FIRE number is the portfolio that can cover your annual expenses at a safe withdrawal rate — 25 times expenses at the classic 4% rate.
Investing
Compound Interest Calculator See how a starting balance plus regular contributions grows with compound interest over time. Investment Growth Calculator Project how an investment portfolio grows when you invest a fixed amount each month. Inflation Calculator See what a future amount of money is worth in today’s purchasing power after inflation. Rule of 72 Calculator The Rule of 72 estimates how many years it takes your money to double at a given annual return. Savings Goal Calculator Find the monthly amount you need to save to reach a target by a chosen date. Time to Reach a Savings Goal Find how long it takes to reach a target — like your first $1 million — at your current savings rate.
Housing
Taxes
Federal Income Tax Calculator (2026) Calculate your federal income tax on a given taxable income, with a clear bracket-by-bracket breakdown. Effective vs Marginal Tax Rate Calculator (2026) Compare your marginal tax bracket with your true effective rate — the two numbers most people mix up. Tax Bracket Calculator (2026) Find out which federal tax bracket your income falls into for 2026. Bonus Tax Calculator Your bonus is withheld at a flat 22%, but your real tax on it depends on your bracket — this shows the gap. Roth Conversion Calculator See the federal tax cost of a Roth conversion and the bracket it pushes you into this year.
Income & Compensation
Education & Family
529 College Savings Calculator Project how a 529 plan grows with regular contributions before college starts. Student Loan Payoff Calculator See how paying extra each month gets you out of student debt faster and cuts total interest. Credit Card Payoff Calculator See how long a credit card takes to pay off and how much extra payments accelerate it.