Market history & backtest

We built this for sanity - one accessible place to compare a century of market history instead of piecing it together from scattered charts and paywalled feeds. Most investing intuition comes from the last decade, and most market history looks nothing like the last decade. So it bundles roughly a hundred years of daily data - major indexes, S&P 500 sectors, gold, and CPI - with the site itself: no account, no API key, and no data leaving your device.

Beyond browsing, it answers "what if" concretely: rebase any set of series to a common starting point to compare eras, or replay an arbitrary list of buys and sells - a lump sum, a monthly DCA plan, a badly-timed entry - and see how the strategy fared against inflation, gold, or simply holding the S&P 500. History is not a forecast, but it is the best antidote to both panic and overconfidence.