The tools desk

Calculators that work for you — not for an ad network.

No email wall, no "unlock your results," no quietly selling your inputs. Nine calculators that run entirely in your browser, show the math behind the answer, and never phone home with your numbers.

No sign-up required Inputs never leave your device Formulas shown in plain English
Investment

Compound Interest

Watch a contribution snowball over decades and see exactly how much of the total is growth versus what you put in.

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Investment

Investment Growth

Project a portfolio with regular contributions, a target return, and a time horizon you control.

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Investment

Savings Goal

Name a number and a deadline; we'll tell you the monthly amount it actually takes to get there.

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Retirement

Retirement

Estimate whether your current pace gets you to the finish line — and what a small bump in savings does.

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Retirement

401(k) Growth

Factor in your contribution, the employer match, and decades of compounding to see your balance at 65.

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Retirement

Net Worth

Add up what you own, subtract what you owe, and get the single number worth tracking once a year.

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Debt

Debt Payoff

Compare avalanche vs snowball, see your debt-free date, and learn what an extra $50 a month really buys.

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Home

Mortgage

Monthly principal and interest, total cost over the life of the loan, and how taxes and insurance shift it.

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Home

Rent vs Buy

The honest comparison — break-even years, not a sales pitch — for renting versus owning your next place.

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Everything runs locally

These calculators are plain JavaScript in your browser. Close the tab and your inputs are gone — there's no server quietly logging your salary or your debts.

We show our work

Every tool explains the formula it uses and the assumptions baked in. If a result surprises you, you can see exactly why.

Estimates, not promises

Markets and rates change. Treat every output as a well-built estimate to inform a conversation — not a guarantee about your future.

Good to know

Calculator questions.

Do these calculators store my information?
No. They run entirely in your browser using JavaScript. Nothing you type is sent to us or to any third party — when you close the tab, the numbers are gone. That's the whole point of building them this way.
How accurate are the results?
The math is exact, but the inputs are assumptions. A retirement projection that assumes a 7% return will be wrong if markets return 4% or 10%. We surface the assumptions so you can stress-test them — and we'd always run a few scenarios rather than trusting a single rosy one.
Which calculator should I start with?
If you're just getting oriented, the net worth and compound interest tools give you the clearest picture fastest — where you stand today, and where consistent investing could take you.
Is a calculator result the same as financial advice?
No. These are educational tools, not personalized advice. They don't know your full situation, your taxes, or your goals. For decisions that matter — a mortgage, a retirement plan — use the output as a starting point for a conversation with a qualified professional.

Numbers in, clarity out.

Run the compound interest tool first — it's the one that tends to change how people think about getting started.