HODL Waves

HODL Waves were first published in April 2018 by Dhruv Bansal, co-founder of Unchained Capital, in "Bitcoin Data Science: HODL Waves." The construction: bucket the entire circulating supply by time since last on-chain move (under 1 day, 1 week, 1 month … 10+ years) and stack the buckets into a daily 100% area chart. Each band's thickness is that age cohort's share of total supply.

At bull-market climaxes supply changes hands en masse, and the young bands (<3 months) suddenly widen. As those top buyers hold on, the cohort ages month by month into progressively older bands — rendering on the chart as a wave propagating upward. The original article named the landmark HODL episodes of 2011 and 2014 this way. Conversely, sudden thinning of old bands means dormant supply is waking — typical of bull-market distribution.

The extremes carry the signal: young-band share spiking to historical highs means turnover mania, historically overlapping cycle tops; sustained widening of the 5y+ and 10y+ bands means deepening supply lockup (lost coins included). Remember that age resets only on on-chain moves — intra-exchange turnover never touches the chain, while custody migrations "rejuvenate" old coins that never truly changed owners. Post-2024 ETF custody reshuffling of old bands needs to be identified separately.

Alongside holder behavior, watch short-term leverage via BTC liquidations and funding rates.