Bitcoin stock-to-flow model chart (BTC stock to flow): circulating supply divided by yearly issuance, turned into a model price by the published S2F regression, plotted against BTC. Updated daily.
Model price steps up at each halving as issuance halves. Log scale.
model price = exp(-1.84) · S2F^3.36 , S2F = circulating supply / issuance over 365 days
Stock-to-flow measures scarcity: the existing supply divided by the new supply produced in a year. Coinfuty rebuilds the supply from the issuance schedule (50 → 25 → 12.5 → 6.25 → 3.125 BTC per block, 144 blocks a day), so the ratio jumps at every halving.
The model price uses the coefficients from the original 2019 S2F paper, unadjusted, so the line matches the commonly quoted version. The deviation is simply price divided by that model.
Price tracked the model loosely through 2013–2021 and has stayed far below it since the 2024 halving pushed the model into the millions. A deviation at or above 1.0× — price catching up with the model — was the hub's peak threshold; it has not been reached in this cycle.
With a stock-to-flow ratio of 122.4, the 2019 model gives $1,642,050. Bitcoin closed at $82,541 on Oct 19, 2026, 0.05× of the model.
Price has stayed far below the model since 2022, and the 2024 halving pushed the model into the millions. Most analysts now treat S2F as a scarcity narrative rather than a price model; Coinfuty keeps it for comparison with the other cycle charts.
Stock is the circulating supply reconstructed from the issuance schedule; flow is the supply added over the previous 365 days. Dividing the two gives the number of years of current issuance contained in the existing supply — about 120 after the 2024 halving.
Coinfuty computes every series on this page from daily BTC close prices and public constants — the Bitcoin halving schedule, block subsidy and published regression coefficients. Values refresh nightly (00:20 UTC) and the current day is patched hourly. These are historical, backward-looking indicators; nothing here is investment advice.