Stock Comparison Tool
Compare the historical price paths of up to five U.S.-listed securities. This is a learning tool for observing volatility, relative performance, and moving averages — it produces no ratings, scores, or signals, and nothing here is a recommendation. The statistical case for skepticism about stock-picking is covered in Index Funds & ETFs vs. Individual Stocks.
Select securities
Time range
Data for informational purposes only; may be delayed. Source: Stooq historical prices via public proxy.
How to read these metrics
These are descriptive statistics about the past. None of them predicts future prices, and decades of research find that simple technical measures like these have no reliable predictive value for individual investors.
- Period change — the percentage difference between the first and last price in the selected range. Sensitive to the exact start date: shifting the window by weeks can flip the story.
- Volatility (annualized) — the standard deviation of period-to-period returns, scaled to a yearly figure. Higher numbers mean larger historical swings in both directions. It measures how bumpy the ride was, not where it was going.
- Simple moving average (SMA) — the average closing price over the last 20 or 50 periods. Analysts use SMAs to describe trends after the fact; a price above or below its SMA is a description, not a signal. Crossover “strategies” backtest poorly once costs are included.
The deeper lesson from comparing securities is usually the one covered in diversification: single names swing far more than broad baskets.