Three replays, computed from the same history
$100 every month, starting…
| Start | Months | Invested | BTC stacked | Value at 2026-08 | Multiple |
|---|---|---|---|---|---|
| 1 year ago (2025-08) | 13 | $1,300 | 0.0160 | $1,007 | 0.77× |
| 5 years ago (2021-08) | 61 | $6,100 | 0.1433 | $9,004 | 1.48× |
| 10 years ago (2016-08) | 121 | $12,100 | 2.0177 | $126,787 | 10.48× |
Numbers regenerate with the nightly rebuild, so this table is always the current replay — not a screenshot from a better year. DCA replays always look best from the bottoms and worst from the tops; that is the point of seeing the real math.
Why replay instead of predict?
Because prediction is the one thing nobody can sell you honestly. A replay makes a different, checkable claim: here is what a boring, scheduled purchase did against the actual history — including the crashes. It also shows DCA's real mechanism: the fixed dollar amount buys more sats when price falls and fewer when it rises, no timing skill required. Whether the future resembles the past is exactly the question no calculator can answer — see the FAQ below, and never treat this page as advice.
Questions people actually ask
What is DCA (dollar-cost averaging)?
Buying a fixed amount on a fixed schedule — say $100 every month — regardless of price. You automatically buy more units when the price is low and fewer when it is high, and you never have to guess the right moment. This tool replays that strategy against bitcoin’s real price history.
Does past performance mean DCA will work in the future?
No, and this page will not pretend otherwise. The results here are historical arithmetic, not a forecast and not financial advice. Bitcoin has had multi-year drawdowns above 80% — any honest replay includes people who started at tops and waited years to break even.
What prices does the calculator use?
First-of-month USD prices from mempool.space’s historical price index, from September 2010 to the current month, with the final value computed at the latest monthly price. The dataset is refreshed with the site’s nightly rebuild.
Why monthly instead of daily or weekly?
Over multi-year horizons the difference between monthly and weekly DCA is noise compared to when you start and how long you stay. Monthly keeps the replay honest, fast and easy to verify by hand.