Stock-to-Flow Ratio
Models Bitcoin's scarcity by comparing existing supply (stock) to annual production (flow). Each halving doubles the S2F ratio.
What is it?
Stock-to-Flow (S2F) divides Bitcoin's existing supply (stock) by annual production (flow = block rewards × 144 blocks/day × 365 days). The ratio measures how many years of current production are already held. The higher it is, the stronger the relative scarcity - gold historically sits around 60, silver around 30. Bitcoin doubles its S2F at every halving, the most visible scarcity mechanic in the protocol.
How to read
The chart overlays two timeseries on a dual axis: left is the S2F ratio (linear scale) plotted in gold, right is BTC price (log scale) plotted in white. S2F forms a staircase that jumps at every halving (2012, 2016, 2020, 2024) ; between halvings, the ratio climbs slowly because supply keeps growing while flow stays fixed. The point is not to predict price - it is to see at a glance the structural correlation between scarcity jumps and post-halving price moves.
Key zones
S2F vertical jumps match halvings: 2012 (S2F ≈ 26), 2016 (S2F ≈ 50), 2020 (S2F ≈ 56 then doubled), 2024 (S2F > 120). The 12-18 months after each jump have historically been strong BTC rally periods, though with decreasing amplitude each cycle (diminishing returns).
What to observe
Watch the 12-18 months following each step: this is the historical 'supply shock' window, when reduced miner issuance starts to bite on market flows. Visually compare the gap between the S2F curve and the price curve: a flat price while S2F keeps climbing may indicate that demand is not absorbing the scarcity - a fragile indication.
Historical context
The previous three halvings (2012, 2016, 2020) were all followed by major BTC rallies within 18 months - but each cycle delivered a lower multiple (100×, 30×, 7×). The 2024 halving marked the S2F transition to a regime >120, the highest in Bitcoin history. The post-halving multiple evolution on this cycle serves as an empirical test of the diminishing-returns pattern.
Expert notes
This deliberately simple view (ratio + price) emphasises the readability of the halving staircase and its visual relation to BTC price. It should not be confused with log-log regression models that try to predict a price level from S2F: those models (PlanB 2019, S2FX) are academically controversial and live in separate tools in the dashboard. Here, we observe the mechanic - we do not bet on it.
Common mistakes to avoid
The S2F ratio is NOT a price prediction. The historical post-halving correlation is descriptive, not causal. Taking a point value of S2F as 'price will be multiplied by X' is an over-interpretation. The model does not account for demand, which remains the dominant factor on short and medium timescales.
Programmatic access
REST API
curl -sS \
'https://api.trinityinsights.io/api/v1/onchain/stock-to-flow/history?days=90' \
-H 'X-API-Key: $TRINITY_API_KEY'MCP server
{
"tool": "get_chart_value",
"metric_id": "stock-to-flow",
"timeframe": "1y"
}Required tier: free. See the pricing grid for the tier list and the MCP documentation for multi-client configuration.
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Institutional disclaimer
Trinity Insights is an educational and analytical tool. The metric above does not constitute investment advice. Trinity Insights is not a Crypto-Asset Service Provider (CASP) registered under MiCA Regulation (EU) 2023/1114. See the full disclaimer.