About the data
Every number on this site traces back to a named source, a known update cadence and a method you can follow. This page lays out openly where the data comes from, how often it refreshes and what we compute ourselves.
Price data
Our own price database holds over 1.5 million records at 5-minute resolution back to 1 January 2012, plus daily data from 18 July 2010 (the start of trading on Mt. Gox). The historical prices come from CoinGecko and a CoinMetrics backfill; the current live price is added every 30 seconds from Coinbase. So we do not produce the price ourselves. It forms on exchanges; our contribution is the fully stored history and the computation on top of it.
The US-dollar prices are real historical data. Euro values are converted from the USD price at each day's ECB reference rate, day-accurate across the entire history.
On-chain transfers
We track large on-chain transfers of 100 BTC or more. Since October 2025 we capture this data continuously from block data (primarily from our own Bitcoin node, with mempool.space as failover), with every new block, roughly every 10 minutes. These are actual movements on the Bitcoin blockchain, not estimates.
Data sources at a glance
The network data comes primarily from our own Bitcoin node; public services act as failover, provide market and price data, and serve as external reference (inflation, gold). Everything is cached on our side and re-served; every source is named:
Blocks & block height, difficulty, hashrate, mempool size and transaction fees, all from our own self-hosted Bitcoin full node with its own mempool instance. Primary source for the network data.
Queried live with a freshness check; automatic failover to mempool.space if it is unavailable.
Failover for the network data when our own node is unreachable. Also the block source for whale transfers (≥100 BTC).
Cached, refreshed every 30-60 seconds.
Market capitalisation, trading volume plus all-time high (ATH) and all-time low (ATL).
Cached, market data every 5 minutes, history hourly.
Exchange rates (BTC → USD/EUR), our primary source for the live price.
Polled and stored every 30 seconds.
Consumer price indices (US, Euro area, Germany): external reference for sats purchasing power (inflation-adjusted values).
Fetched daily and stored on our side; CPI is released monthly.
Gold price (XAU/USD): external reference for sats purchasing power (value in gold).
Fetched on business days and stored on our side.
Computed metrics
Some metrics we compute ourselves from the current block height, with no external licence or third party. These include circulating supply, the share of coins already mined (% mined), the stock-to-flow ratio and energy per BTC. The formulas are publicly known and derive directly from block height.
Not financial advice
Everything on onlytwenty.one is for information only and is not investment, financial, legal or tax advice. Past performance is no guarantee of future results. Bitcoin is volatile, and you can lose some or all of the capital you commit. Do not make financial decisions based on this site alone. Do your own research and, where appropriate, seek independent, qualified advice.