MoneyMath

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Know your FIRE number before you sign up.

There's no sign-up. Type three numbers, watch the answer compound in front of you. 27 calculators for early retirement, side income, and the real cost of everything.

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Coast FIRESaved on this device only
Your money compounds by 65 to

$1.28M

If you never save another dollar, compounding alone clears your $875K FIRE number by 65.

FIRE number
$875K
Years to spare
5.6
FIRE family

When can you stop working?

Four flavors of financial independence. Same math, different lifestyle bets.

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Income & Wealth

What you make. What you keep.

Your real hourly rate, what to charge clients, what you're worth, and what the IRS takes.

Selling & Reseller

What marketplaces actually take.

eBay, Etsy, Mercari, Poshmark — every fee on a sale, your net payout, and the breakeven price.

Investing

What money does over time.

Compounding, annualized returns, and inflation — the three forces that decide what your money becomes.

Debt & Costs

What things actually cost.

Money flowing out — over the full term, not the sticker. Loans, recurring obligations, big purchases.