Guides / Glossary / Full node
Glossary

Full node: checking the chain yourself

A computer running software that checks every block and transaction against the rules, without trusting anyone else.

Education only

Definition. A computer running software that checks every block and transaction against the rules, without trusting anyone else.

How it works

A full node downloads every block from other nodes and checks each one: that the proof of work is valid, that every transaction spends coins that exist and have not been spent, that signatures are correct and that no more new bitcoin is created than the rules allow. A node that finds a rule broken rejects the block, whoever mined it. Bitcoin Core is the most widely used full node software, and bitcoin.org sets out typical requirements for disk space, memory and bandwidth.

A pruned node performs exactly the same checks but then deletes older block data to save disk space. It still enforces the rules, but it cannot serve old blocks to others or rescan old history for a newly imported wallet.

Why it matters for a company

Most wallet apps ask someone else's server for balances and history. That works, but the company is trusting the server's answers and telling it which addresses belong to the company. Connecting the company's watch-only wallet and signing software to its own node removes both problems: the balance is checked against the rules locally, and no outside server learns the company's addresses.

A node also gives the company an independent source for confirmations, fee estimates and incoming payments. For audit purposes, it is a way to show that balances were read from the chain directly rather than from a provider's website.

There are costs: a computer that stays on, storage, updates and someone responsible for it. The site's node page compares common set ups neutrally, including licence terms that matter for business use.

Example only, fictional. A company runs Bitcoin Core on a small office computer, verifies the download signatures before installing, and points its watch-only wallet at it. The IT lead applies updates monthly and records them.

Common mistakes

Sources

Primary sources only. Each link was checked on 9 November 2026. Rules change, so confirm the current version with your adviser.

  1. Bitcoin.orgRunning a full node: what a full node is, minimum requirements, bandwidth and pruning
  2. Bitcoin CoreDownload Bitcoin Core and verify the release signatures
  3. Bitcoin developer documentationGlossary: one bitcoin equals 100,000,000 satoshis
  4. Sparrow WalletConnect Sparrow to Bitcoin Core
Education, not advice.

This is general information and education only. It is not financial, investment, tax, accounting, legal or regulatory advice, and it is not a recommendation to buy, sell or hold bitcoin or any other asset. It does not take account of your circumstances or those of your company. You must obtain your own official professional advice to confirm this information is correct before acting on it.

Rules change. This information is correct to our understanding at the last-reviewed date, but it may be incomplete or out of date, and official sources take precedence. Bitcoin is volatile. A company that buys it could lose some or all of the money it puts in.

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