Guides
Plain-English, data-backed guides on backtesting, portfolio strategy, risk, and retirement — each one tied to a free tool you can run on your own holdings.
How to Backtest a Portfolio: A Free, Step-by-Step Guide
What backtesting is, how to run one in minutes, how to read every metric, and the common mistakes that make a backtest lie to you.
Read the guide →StrategiesThe 60/40 Portfolio: Returns, Drawdowns, and Whether It Still Works
The logic behind 60% stocks / 40% bonds, how it held up through every recent crash, the 2022 problem, and how to test it on your own numbers.
Read the guide →Risk & diversificationHow to Tell If Your Portfolio Is Actually Diversified
Why owning more funds doesn't mean diversified, how correlation measures it, why it fails when you need it most, and how to check your holdings.
Read the guide →RetirementThe 4% Rule, Explained: How Long Will Your Retirement Savings Last?
Where the 4% rule comes from, why it's only a starting point, why sequence risk is the real danger, and how to test your own number.
Read the guide →StrategiesThe Efficient Frontier, Explained (Without the Math Headache)
The risk-return tradeoff made visual: what the frontier is, the two portfolios everyone cares about, and the catch to watch for.
Read the guide →StrategiesLump Sum vs Dollar-Cost Averaging: What the Data Says
Whether to invest a windfall all at once or spread it out — what history favors, and why the right answer is partly about your stomach.
Read the guide →StrategiesLazy Portfolios, Explained: Simple Index Mixes That Beat Most Investors
A handful of low-cost index funds, set-and-forget — why it works, the classic recipes, and how to test one on real data.
Read the guide →RetirementHow Much Do I Need to Retire? A Simple Way to Find Your Number
The 25x rule of thumb, why your spending drives the number, what shifts it, and how to pressure-test your own plan.
Read the guide →Risk & diversificationMaximum Drawdown: Why the Worst Loss Matters More Than the Average Return
The largest peak-to-trough loss — why it's the number that makes people sell, how it differs from volatility, and how to measure yours.
Read the guide →Risk & diversificationThe Sharpe Ratio, Explained: Are You Being Paid for the Risk You Take?
Return per unit of risk, in plain English — the formula, what counts as good, its blind spots, and how to see yours.
Read the guide →Getting startedMonte Carlo Simulation, Explained: Planning for a Range of Futures
Why one average projection lies, what running thousands of scenarios tells you, and how to read the probability of success.
Read the guide →Getting startedStocks vs Bonds: How They Differ and How to Mix Them
Ownership vs lending, growth vs ballast, and how to choose the split that fits your timeline and nerves.
Read the guide →Getting startedHow to Read a Stock's Fundamentals (Without an Accounting Degree)
The handful of numbers that describe the business behind a ticker — growth, profitability, health, valuation, dividends — in plain English.
Read the guide →StrategiesPortfolio Rebalancing, Explained: Why and How to Reset Your Mix
Why your mix drifts, how resetting it controls risk and enforces discipline, and the simplest ways to do it.
Read the guide →StrategiesVOO vs VTI: S&P 500 or Total US Market — Does It Matter?
Two popular index ETFs that are more alike than different — what each holds, the real distinction, and how to check it yourself.
Read the guide →StrategiesAsset Allocation by Age: How Your Mix Should Change Over Time
Why your mix should shift from growth toward stability over time, the rules of thumb, and what actually matters more than age.
Read the guide →Getting startedIndex Funds vs ETFs: What's the Difference and Which Should You Pick?
Same holdings, different wrapper — how they trade, automate, and get taxed, and why the holdings matter more than the label.
Read the guide →Risk & diversificationShould You Invest Internationally? Home-Country Bias, Explained
Why most investors overweight their home market, the real case for going global, and how to check the diversification benefit yourself.
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