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 about 1.52 million records at 5-minute resolution, reaching back continuously to 1 January 2012. The current live price is added every 30 seconds from Coinbase.
Honest note on euro values: the US-dollar prices are real historical data. Euro values before roughly 2024 are converted from the USD price at a reference rate - a point-in-time EUR/USD exchange rate is not available for the deep history. For the more recent past the euro values reflect the actual exchange rate.
On-chain transfers
We track large on-chain transfers of 100 BTC or more. This data has been captured continuously since October 2025 from mempool.space block data - with every new block, roughly every 10 minutes. These are actual movements on the Bitcoin blockchain, not estimates.
Live network data
These figures come from established public services; we cache them briefly and re-serve them. That keeps the displays fast and the providers unstrained. Every source is named:
Blocks & block height, difficulty, hashrate, mempool size, transaction fees and Lightning statistics.
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.
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.
Who runs this
onlytwenty.one is operated and maintained by a single person. Exactly who - with a full address and contact details - is stated openly in the imprint.