Reference

How we calculate the numbers

Last updated: 4 June 2026

WHAT IF estimates what a one-time, hypothetical purchase made in the past would be worth today. The math is deliberately simple and transparent. This page documents the data, the formula, and — just as importantly — what the numbers leave out.

The core idea

You choose an amount, an asset, and a time horizon. We find the asset's price at the start of that horizon (the "entry price") and its price today, then assume you bought as many units as your amount could afford at the entry price and held them, unchanged, until now.

The formula

For an investment amount A, entry price P₀, and current price P₁:

• Units held = A / P₀
• Value today = (A / P₀) × P₁
• Profit / loss = Value today − A
• Return % = (P₁ − P₀) / P₀ × 100

The leaderboard runs this same formula across every asset over the same window so you can compare them on an equal footing.

Where the data comes from

Crypto and gold use daily closing candles (weekly for multi-year windows) and a live 24-hour ticker. Indices and stocks use Yahoo Finance adjusted daily closes, so stock splits (for example NVIDIA's 10-for-1 in 2024 and Tesla's 3-for-1 in 2022) and dividends are reflected without creating artificial jumps in the price history. Live prices refresh roughly once a minute; historical series are cached for several hours because they barely change intraday.

Time horizons

Available windows are 1 month, 3 months, 6 months, 1 year, 2 years, 3 years, and 5 years, measured back from today. The "entry price" is the close nearest the start of that window.

Caching and reliability

To stay fast and avoid rate limits, prices pass through an edge cache and your browser's local storage. If a live source is briefly unreachable, the Site falls back to a recent cached snapshot so it keeps working. As a result, a value may occasionally lag the absolute latest tick by up to a minute or two.

What the numbers leave out

• Fees & spreads — exchange fees, bid/ask spreads, and network costs are excluded.
• Taxes — capital gains and other taxes are not modelled.
• Slippage — we assume you could buy and sell exactly at the listed price, which large or illiquid orders cannot.
• Staking & yield — crypto staking rewards and lending yield are not added. Stock and index figures use adjusted close, so dividends are reflected; crypto and gold are price-only.
• Currency — values are shown in US dollars.
• One purchase, held — we model a single lump-sum buy with no rebalancing or further trades.

Accuracy and honesty

Third-party data can be delayed, revised, or briefly wrong, and our assumptions simplify reality. Treat every figure as a ballpark for curiosity and comparison — not a precise record of what you would have netted. WHAT IF is informational and is not financial advice; see our terms & disclaimer.