Is Bitcoin Correlated With the Stock Market?

Is Bitcoin correlated with the stock market? The short answer is that it depends on when you ask, and that the honest version of the answer is more useful than any single number.

There is no one correlation

Correlation is not a fixed property of two assets. It is a statistic computed over a chosen window of time, and different windows produce different answers. For long stretches of its history Bitcoin behaved idiosyncratically, moving on adoption news, crypto-specific events, and its own supply narrative, with little steady relationship to equities. In other stretches it has tracked stock indices closely. Both are true; they are just true at different times. So a sentence like "Bitcoin has a correlation of X with the Nasdaq" is quietly hiding the window it was measured over, and the window is doing all the work.

When the link tightens

The clearest example came during the 2022 monetary tightening. As central banks raised rates and markets repriced risk across the board, Bitcoin and technology-heavy equity indices began moving almost together. The reason was not that Bitcoin had become a tech stock, but that in a regime dominated by interest-rate expectations, nearly everything with risk attached becomes a single macro trade. When the tide is liquidity, most boats move with it. In calmer regimes, when macro is not driving everything, the relationship loosens again and Bitcoin drifts back toward its own behaviour.

Why this matters for diversification

Many people hold Bitcoin partly as a diversifier, something that will not move with their equity exposure. The moving nature of correlation is exactly what makes that fragile. Correlations between risk assets tend to rise toward one during sharp risk-off shocks, which is the precise moment a diversifier is supposed to earn its place. The asset that looks uncorrelated across a calm sample can become highly correlated in the crash you were diversifying against, because fear is a common factor that pulls otherwise unrelated things into the same direction. Diversification measured in good weather can quietly evaporate in bad.

The general lesson

Bitcoin's relationship with equities is a specific case of something that applies to everything you measure. A correlation, an edge, a setup's win rate, are all estimates over a window, and they are free to behave differently outside it. Treating a windowed number as a permanent fact is one of the most common ways traders and investors get blindsided by a change that was always possible. The number was never a constant; it was a snapshot. The habit worth building is to ask over what period, under what conditions, and how stable, rather than accepting a single figure as the property of the thing. That question, applied to a trading edge, is what our case study is about.