What is realized volatility?

Realized volatility measures how much the price actually moved. We take the daily log returns over the last 30 or 90 days, calculate their standard deviation and annualise it (× √365). A reading of 50% means Bitcoin’s typical yearly swing is about ±50%.

Why traders watch it

Volatility moves in cycles. Long periods of very low volatility are often followed by sharp breakouts in either direction, while volatility spikes usually come with crashes or blow-off rallies. Compare it with the implied volatility (DVOL) chart to see what the options market expects next.