What is a node in crypto, and what does it actually do?

A node is a computer running a blockchain's software. It keeps its own copy of the ledger, checks every new transaction and block against the network's rules, and passes the valid ones on to other nodes.

A blockchain has no central server. The network is simply thousands of these nodes, each holding the same copy. Anyone can run one, though most people never need to, because their wallet quietly talks to a node someone else runs.

How do crypto nodes work?

A blockchain is a shared record of who sent what to whom, kept in many places at once instead of in one bank's database. If that idea is new to you, it helps to read how cryptocurrency and blockchain work first.

Nodes are those "many places". Follow one payment and you can see what they do with it. Say Maria sends 0.01 BTC to a friend:

1. Maria's wallet signs the transaction and hands it to a node. The wallet doesn't write anything to the blockchain itself; it needs a node to carry the transaction into the network.
2. The node checks the transaction. It looks at whether the signature is valid, whether those coins exist and whether they have already been spent. A transaction that fails any check is dropped on the spot.
3. The node passes the transaction on. Neighbouring nodes run the same checks and forward it further, until it sits in the mempool of nodes across the network. The mempool is each node's waiting room for transactions that aren't in a block yet.
4. A miner puts the transaction into a block. On Bitcoin a new block appears roughly every 10 minutes, and miners pick the transactions that pay the best fee first.
5. Every node checks the new block and adds it to its copy. Only now does Maria's payment count as confirmed, and each later block adds one more confirmation on top.

Nobody coordinates this. Each node trusts its own checks, not the word of the others. That is why the same history ends up in every copy: a node that tried to slip in a fake balance would simply be ignored by the rest.

You can watch the result yourself. A block explorer is a website that reads data from nodes and shows it in plain view, so the steps above appear there as statuses: pending while the transaction waits in the mempool, then confirmed, with a count that grows block by block. Here is how to read a transaction in a blockchain explorer.

Why a network needs thousands of copies

A single copy of the ledger could be edited, switched off or blocked by whoever owns it. Thousands of independent copies can't. To change history, someone would have to get almost every node to accept the change, and each node checks for itself.

The same goes for the rules. Bitcoin's limit of 21 million coins doesn't hold because some company promises it. It holds because every node rejects a block that creates more coins than the rules allow. The more nodes there are, run by more people in more places, the harder the network is to shut down or censor.

What types of blockchain nodes are there?

"Node" is a role, not one kind of machine. Networks use several types of nodes, and they differ in what they store and what they are allowed to do:

• Full node. Downloads every block from the very first one and checks each against the rules. It takes nothing on trust and can answer any question about the chain.
• Pruned node. A full node that checks everything, then deletes old blocks to save space. On Bitcoin it needs roughly 10–12 GB instead of the whole chain, because the record of coins that haven't been spent yet stays in full.
• Archive node. A full node that also keeps every past state of the chain, meaning what each balance was at every block. Explorers, analytics firms and developers need this; on Ethereum it takes terabytes of disk.
• Light node. Downloads only block headers, the short summaries of each block, and asks full nodes for the rest. This is the kind that fits on a phone.
• Mining node. On proof-of-work networks such as Bitcoin, where miners compete by spending electricity, this is a node tied to mining hardware that builds new blocks.
• Validator node. On proof-of-stake networks such as Ethereum, where the right to add blocks comes from locked-up coins, this is a node whose owner has put down a deposit to propose and confirm blocks.
• Masternode. On a few networks, such as Dash, a node backed by a large coin deposit that does extra work for the network and receives a share of block rewards.

Two pairs from this list are worth a closer look, because people mix them up: full and light nodes, and full nodes versus the machines that actually produce blocks.

How is a full node different from a light node?

The difference is how much each one takes on trust. A full node checks every block itself. A light node checks that a transaction made it into a block, but assumes the block follows the rules because the full nodes it talks to accepted it. The idea goes back to the Bitcoin white paper of 2008, which called it simplified payment verification.

Here is how that looks in practice. Maria's friend runs a full node: when 0.01 BTC arrives, his own machine has checked the whole chain behind it. Maria uses a light wallet on her phone: she knows the payment arrived because the full nodes her wallet asked say so.

For everyday amounts the light approach works fine, and it is the only one that fits on a phone. The price is trust and privacy: the full node you ask learns which addresses you are interested in.

Some wallets are not nodes at all. They send every request to a node run by the wallet company or a hosted provider, and show you what that node answers. MetaMask, for example, connects to a provider's node by default, and you can point it at a different one in its network settings.

How is a full node different from a miner or a validator?

A full node checks. A miner or a validator also produces blocks, and has something to lose if it cheats:

• A Bitcoin miner spends electricity on specialised hardware to win the right to add the next block. The winner collects newly created coins plus the fees from the transactions in that block.
• An Ethereum validator locks 32 ETH as a deposit and runs validator software on top of a full node. The network picks validators to propose blocks and others to vote on them; validators earn ETH for this work, lose small amounts for being offline, and get penalised and forced out for signing conflicting blocks or votes.

What miners can't do is change the rules. Suppose a miner builds a block that pays itself more than the rules allow. The work behind the block is real and the electricity is spent, yet every full node rejects the block anyway. The miner loses the reward, and the chain carries on without that block. That is why full nodes, not miners, have the last word on what counts as valid Bitcoin.

Can you run your own Bitcoin node?

Yes. Bitcoin Core, the main node software, is free and runs on Windows, macOS and Linux. You don't need special hardware, just room on the disk and a decent connection.

Here is what the computer needs, as of October 2026:

• Disk. The full chain takes over 750 GB and grows every day, so a 1 TB SSD is the practical size. A pruned node gets by with roughly 10–12 GB, and that figure slowly grows too.
• Memory. At least 2 GB of RAM.
• Download. Roughly 740 GB for the first sync, then about 20 GB a month.
• Upload. At least 400 kilobits per second and no tight monthly cap; a busy node can upload 200 GB or more a month.
• Time online. At least six hours a day, and a node that runs all the time is more useful to the network.

The first start is the slow part. The node downloads and checks every block since 2009 before it is ready, which takes from hours on a fast machine to days on a small one. After that it keeps up with each new block as it arrives.

An Ethereum node asks for noticeably more:

• Two programs. Since Ethereum moved to proof of stake, a node runs an execution client and a consensus client side by side.
• A fast, big disk. At least a 2 TB NVMe SSD, and the requirement keeps growing.
• More memory. At least 16 GB of RAM, with 32 GB recommended.

Why bother, if a wallet works without one? A node of your own gives you three things:

• You verify your own payments. Your wallet connects to your node, and "received" means your own machine checked it.
• You keep your privacy. No outside server learns which addresses you watch.
• You strengthen the network. One more independent copy that enforces the rules.

A business that wants to accept bitcoin directly meets the same question at a bigger scale. Self-hosted payment software for bitcoin watches for incoming payments through a node, and the business keeps that node synced, updated and online itself. A hosted gateway runs that part for it. Which way pays off depends on volume and on who will look after the server, and here is how to decide whether to self-host a crypto payment gateway or plug in a hosted one.

Do Bitcoin nodes get paid?

No. Running a Bitcoin full node earns nothing: the protocol has no reward for it and no share of fees. People run them for the reasons above.

The money in Bitcoin goes to miners. Each block brings its miner a fixed amount of new coins, 3.125 BTC since the April 2024 halving, plus the fees users attached to the transactions in that block.

Some networks do pay for running a node, but always for work and usually against a deposit:

• Proof-of-stake validators. On Ethereum the deposit is 32 ETH, and rewards are paid in ETH. Staking pools let people with less than 32 ETH take part through someone else's validator.
• Masternodes. On Dash a regular masternode locks 1,000 DASH and receives regular payments from block rewards.
• Node providers. Companies run nodes for wallets, exchanges and apps and charge them for access, a business often sold as "node as a service". The income comes from customers, not from the network.

Be careful with offers of "crypto nodes" as passive income. A real network pays node operators under its own published rules, for work it can check. If a project sells you a "node licence" and the promised return comes from the project rather than from the network, your income depends entirely on that project.

For anyone who simply sends crypto, the practical side of all this is the fee. It is the only payment the network takes from you, and where it ends up depends on the network:

• On Bitcoin, the whole fee goes to the miner who puts your transaction into a block.
• On Ethereum, the base fee is burned, meaning destroyed for good, and only the tip you add on top goes to the validator who proposes the block.

The network fee is only one layer of what a crypto payment can cost, and the other layers sit in how network fees, gas and gateway fees add up on a crypto payment.

The short version

A node is a computer that holds a copy of a blockchain and checks it against the rules. Together, nodes are the network: they pass transactions along, reject anything that breaks the rules and agree on one shared history.

Full nodes check everything, light nodes trust full nodes, and miners and validators produce the blocks. Anyone can run a Bitcoin node on an ordinary computer with a 1 TB drive. It won't pay you, but it lets you check your own money without asking anyone.

Questions people ask next

How much does it cost to run a crypto node?

The software is free, so the cost is the hardware and the electricity. A Bitcoin full node runs on a computer you may already own plus a 1 TB SSD. An Ethereum node needs a stronger machine with a fast 2 TB drive and 16–32 GB of RAM, and running a validator on top of it means locking 32 ETH.

Can I run a Bitcoin node on a Raspberry Pi?

Yes. A Raspberry Pi 4 or 5 with an external 1 TB SSD meets Bitcoin Core's requirements, and several ready-made node packages are built for exactly this setup. Expect the first sync to take longer than on a desktop computer.

How many Bitcoin nodes are there?

Public node counters currently see about 26,000 Bitcoin nodes that accept connections from others. The real number is higher, because many nodes sit behind home routers and don't accept incoming connections, so the counters can't reach them.

Which cryptocurrencies let you run a node?

Any public blockchain lets anyone download its software and run a full node. What differs is what that takes and whether it pays: a Bitcoin node needs a modest computer and earns nothing, while validators on proof-of-stake networks need a deposit and get rewards for their work.