Money Guides
Practical explanations of the math behind everyday money decisions. Each guide walks through the formula, a worked example and the calculator that does the work for you.
Featured guides
Featured guides
How Compound Interest Works: Formula, Examples & Calculator
Learn how compound interest works, the A = P(1 + r/n)^(nt) formula, monthly vs yearly compounding, and two worked examples you can check with a free calculator.
How Much House Can I Afford? A Practical Guide
See how income, debts, down payment, interest rate, taxes, insurance and HOA dues shape home affordability, with worked examples and a free affordability calculator.
How Much Should I Save for Retirement? A Practical Guide
Understand the assumptions behind retirement savings targets — contributions, time, growth, inflation, employer match and withdrawals — with example scenarios and free calculators.
All money guides
How Compound Interest Works: Formula, Examples & Calculator
Learn how compound interest works, the A = P(1 + r/n)^(nt) formula, monthly vs yearly compounding, and two worked examples you can check with a free calculator.
How Much House Can I Afford? A Practical Guide
See how income, debts, down payment, interest rate, taxes, insurance and HOA dues shape home affordability, with worked examples and a free affordability calculator.
How Much Should I Save for Retirement? A Practical Guide
Understand the assumptions behind retirement savings targets — contributions, time, growth, inflation, employer match and withdrawals — with example scenarios and free calculators.
How to Calculate Net Worth: Formula, Examples & Tips
Learn the net worth formula, which assets and liabilities to include, how to value a home or car, and why tracking net worth over time is useful — with worked examples.
APR vs Interest Rate: What's the Difference?
Learn why a loan's APR is often higher than its interest rate, how fees affect APR, and how to use both when comparing mortgages, personal loans and credit cards.
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