Guides

Guides

The reasoning behind the calculator, explained without jargon.

All guides

Plain explanations of the ideas behind the calculator, with the numbers worked out.

How compound interest actually works

The mechanism, the formula, how much compounding frequency matters, and why a 25-year-old who saves for ten years beats a 35-year-old who saves for thirty.

What rate of return should you actually assume?

The last decade returned far above the historical average. Using it as a forecast is the most common planning mistake, and the most expensive one.

How much do you need to invest to reach $1 million?

Worked backward by starting age, with the inflation caveat most articles leave out.

What ETF fees really cost over 30 years

Expense ratios compared across common funds, why QQQM beats QQQ for long-term holders, and what a 1% fee actually takes.