Index · 34 tools
Calculators
Every calculator is free, works entirely in your browser, and gets its own dedicated page so you can bookmark or share it. Inputs are preserved in the URL — not sent anywhere, not stored.
Saving & investing
Compound Interest
See how a starting balance and monthly contributions grow over time.
Millionaire Timer
Live countdown to your next big milestone given current savings and growth.
Savings Goal
Find out exactly how long it takes to reach any savings target.
Inflation
See how inflation erodes purchasing power over time.
Cost of Waiting
See the compounding penalty of delaying investing — two investors, one head start.
Emergency Fund
Get a personalized months-of-expenses target based on your income stability and risk factors.
HSA Triple-Tax
See how the HSA's triple tax advantage stacks up against a 401k and taxable account.
DCA vs Lump Sum
Drip a windfall in over months or invest it all at once — see what each path is worth.
Net Worth
Total your assets and liabilities to get a clear snapshot of your financial position.
I-Bond Calculator
See your composite rate, total value at redemption, and effective APY for any hold period — with the early-withdrawal penalty factored in.
Rule of 72
Instantly estimate how many years it takes for any investment to double — and see every doubling milestone after that.
Retirement
Retirement / FIRE
Project your path to financial independence and see when income covers expenses.
401k vs Roth
See which wins on an after-tax basis based on your current and future tax rates.
Safe Withdrawal Rate
Stress-test the 4% rule — see how long your portfolio lasts across three return scenarios.
FI Number
Your work-optional portfolio target — and the years it takes to get there.
Mega Backdoor Roth
Maximize your Roth savings beyond normal IRA limits using after-tax 401k contributions.
Social Security
Find your break-even age for claiming at 62, 67, or 70 — and total lifetime benefits.
Roth Conversion Ladder
Plan your 5-year Roth conversion ladder — see when each conversion becomes tax-free.
Income & taxes
Paycheck
Watch your gross pay flow into taxes, retirement, and take-home.
Inflation-Adjusted Salary
Compare nominal salary growth against real purchasing power year by year.
Real Hourly Wage
Your honest hourly rate after commute, work expenses, and unpaid hours come out.
RSU vs Salary
See the after-tax value of your RSU vest schedule versus equivalent cash compensation.
ESPP ROI
Calculate the guaranteed gain from your Employee Stock Purchase Plan discount and look-back.
AMT Calculator
Find out if you owe Alternative Minimum Tax and by how much — before you file.
Effective Tax Rate
See exactly how much of a raise actually gets taxed — and why your effective rate is always below your marginal bracket.
Borrowing
Mortgage
Full monthly payment — taxes, insurance, HOA, PMI — plus closing costs and the interest split.
Debt Payoff
Compare snowball vs. avalanche strategies across all your debts.
Student Loan
See your payoff timeline and how extra payments save interest and years.
Mortgage Payoff vs Invest
Should you pay down your mortgage early or invest the extra cash? Compare net worth over time.
Spending & big decisions
Rent vs Buy
Compare renting and buying a home over the long run — including the break-even year.
Car Lease vs Buy
Compare the true total cost of leasing versus buying a car over any period.
True Cost of Car
The sticker price is just the start — see the full five-year cost broken down by category.
Home Affordability
Find the maximum home price your income supports, with a live PITI payment breakdown.
Cost of Raising a Child
Year-by-year spending from birth through age 17, broken down by housing, childcare, food, and more. Adjusts for income bracket and family size.