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Math of Money

Know your numbers before you sign anything

38 free calculators for mortgages, retirement, loans, and taxes — with real amortization schedules and charts, not just a single number.

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How it works

Three steps, no surprises

STEP 01

Enter what you know

Amounts, rates and dates. Units are always labelled.

STEP 02

Move one number

Sliders update the result instantly so you can feel the trade-off.

STEP 03

Read the working

Every result shows its formula and a year-by-year table.

Why Math of Money

More than one number

Real charts

Balance over time, payment breakdowns, and year-by-year comparisons.

Full amortization schedules

Every payment for the life of the loan, monthly or yearly.

PDF reports

A clean, printable report of your inputs, results, and schedule.

Scenario comparison

Line up 2–3 versions of a calculation side by side.

Share links

Send a read-only link to your results — no account needed.

Save with Google

Sign in to keep your calculations across devices.

Built to be trusted, not to sell.

Nothing leaves your device
Calculations run in your browser. No account, no tracking of the numbers you enter.
Formulas on the page
Standard, published formulas, printed under each result.
No products to sell
We don’t recommend lenders or funds. The numbers are the product.

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