Nodes: who checks the rules

A node is a computer running Bitcoin software. It downloads the whole record, checks every block and payment from the very first one against the rules, and passes valid ones on to other nodes. Nobody has to trust anyone else's copy: each node checks for itself. To save time, Bitcoin Core by default skips re-checking signatures in older blocks that its code already vouches for; everything else is still checked, and the shortcut can be switched off.

Live from the chain

What a node seesLoading live figures…

Newest block it has checked

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Added

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Payments in it

…each one checked against the rules

Every chain figure on this site, such as blocks, payments, fees and hashrate, comes from a node like this one, which keeps a full copy of the record. Prices come from a public market feed, not from the node.

See it on satoshis.watch →

Nodes and miners do different jobs

Miners	Propose new blocks and are paid for it.
Nodes	Decide whether each block is valid. A block that breaks a rule, such as paying its miner too much or spending coins twice, is refused by every node checking the rules, however much work went into it.

Nodes don't all run the same software. Several programs exist, including Bitcoin Core and Bitcoin Knots, and normally they accept exactly the same blocks. In August 2026 they didn't: nodes running a proposed rule change, BIP-110, rejected block 961,632 and the blocks built on it, and ended up on a separate branch that very little mining power built on. See forks and upgrades.

Miners run nodes too, but most nodes belong to people and businesses who don't mine. Public counts find tens of thousands of them around the world, and more that don't accept outside connections.

Why people run one

• To check for themselves. A node shows that a payment to you is real and how many confirmations it has, without asking a company.
• Privacy. A wallet connected to your own node doesn't tell outside servers which addresses are yours.
• To help. Every node that relays blocks and payments makes the network a little harder to disrupt.

What it takes

The record is large, and it grows by a block about every ten minutes. On a full node in late October 2026 the blocks themselves took about 779 GB. Undo data, kept so the node can step back a block if needed, took about 109 GB more, and the list of unspent coins about 12 GB: around 900 GB in all. Optional indexes, such as one for looking up any transaction, add tens of gigabytes more.

A home computer or a small dedicated box with a large drive can run a node. The first download and check can take from several hours to several days, depending mostly on the drive, the memory and the connection.

A pruned node checks everything the same way, but throws away old blocks once they have been checked. It can keep as little as 550 MB of blocks, though with the coin list it still needs about 15 GB in practice, and it can't keep an index of every transaction.

What your wallet app relies on

Most phone wallets don't run a full node. They ask a server, often their maker's, about your addresses and show what those servers report. Satoshi's paper described this lighter way of checking payments in 2008. It works, but it means trusting the server's answer, and the server learns which addresses are yours. Many wallets let you connect to a node of your own instead.