A bitcoin node is a computer running Bitcoin software that downloads every block, checks every transaction in it against Bitcoin’s rules, and keeps a copy. If you have worked through the first three courses and the Lightning lessons, running your own bitcoin full node is the next step toward using Bitcoin on your own terms. So why run a bitcoin node? Because it is the way to check your own transactions instead of asking someone else’s server.
When your wallet uses a third party’s server, you trust that server to tell you the truth about your balance and your payments. You also show it your addresses, balance and payment history. Your own node fixes both, as long as your wallet is set to use it.
Why Run a Bitcoin Node?
There are four main reasons, each about a different part of what makes Bitcoin valuable.
Verify Your Own Transactions Without Trusting Anyone
Bitcoin’s motto is “Don’t trust, verify.” Yet most users still trust someone else to verify for them. A phone wallet connected to a public server asks that server whether a payment is valid and confirmed, and believes the answer.
With your own node, your wallet asks your own copy of the blockchain, which your machine has checked against every rule. Nobody can tell you a payment confirmed when it didn’t, or that coins you received are valid when they aren’t.
Protect Your Financial Privacy
When your wallet connects to a public Electrum server (a server that keeps an index of the blockchain and answers wallets’ questions about their addresses) or a block explorer, the operator can see:
- every address your wallet asks about, and so your full balance
- your IP address, and so your approximate location
- your transaction history and spending patterns
- when you are online and using your wallet
That data can be logged, sold or handed to authorities. When your wallet connects to your own node instead, those questions stay on your home network. This only works once your wallet is actually pointed at your node; a node your wallet doesn’t use protects nothing. Lesson 4.7 shows how to connect it. More in our guide on running Bitcoin nodes at home for privacy and performance.
Contribute to Network Decentralization
Nodes don’t vote. Each full node simply applies its rules and refuses any block that breaks them, whoever mined it. The more people do this independently, the harder it is for any company, miner or developer group to change the rules without users going along. How much that weighed in past disputes is argued about; what is not in doubt is that your node decides which blocks you accept. Our lesson Who Enforces Bitcoin’s Rules, and How Do They Change? explains what nodes, miners and developers each control, with the 2017 SegWit2x dispute and the 2026 BIP-110 split as examples.
Full Sovereignty Over Your Bitcoin Experience
With your own node, you don’t depend on any company’s servers staying online. If an exchange goes down, a popular block explorer is unreachable or a wallet company shuts its servers, your node keeps working and you keep direct access to the Bitcoin network.
What Does a Bitcoin Node Do?
A full node does several jobs at once.
Downloads and Verifies Every Block Since Genesis
When you first start a node, it connects to other nodes and downloads the whole blockchain, from block 0 (the genesis block, mined on 3 January 2009) to the latest. In November 2026 that is more than 970,000 blocks and roughly 800 GB of data: about 779 GB on 28 October 2026, growing about 80 GB a year (blockchain.com).
During this first sync, called the Initial Block Download (IBD), your node checks every transaction against Bitcoin’s rules: that no coins were created out of nothing, that every signature is valid, that no coin was spent twice, and that the supply follows the schedule that ends at 21 million. To save time, Bitcoin Core by default skips the signature check in older blocks, up to one that each release marks as valid; every block after it is checked in full (the setup lesson explains this setting, called assumevalid).
Enforces Consensus Rules Independently
Your node doesn’t ask anyone what the rules are; they are built into the software you run. If a miner produces a block that breaks them, for example one that pays itself 100 BTC instead of the correct reward, your node rejects it, even if most of the network’s mining power produced it. Mining power only decides between chains that your node already considers valid.
This also means that the software you choose decides which rules you enforce. Most nodes run Bitcoin Core. In 2026 that choice mattered: since August 2026, nodes running some versions of Bitcoin Knots, an alternative to Bitcoin Core, may follow a different chain from the one Bitcoin Core follows, and the two sides describe what happened in opposite terms. The rules lesson linked above tells that story; if you run Knots, our article on the BIP-110 split shows how to check which chain your node is on.
Relays Transactions and Blocks
Once synced, your node passes new transactions and blocks to other nodes, which keeps the peer-to-peer network connected.
Optionally Serves Light Clients
A node can serve data to light wallets that don’t store the blockchain themselves, but Bitcoin Core doesn’t do this by default: both ways of serving them (BIP 37 bloom filters and BIP 157 compact block filters) are off unless you switch them on (Bitcoin Core source). Out of the box, your node serves your own wallets and shares blocks with other full nodes.
Full Node vs Pruned Node vs Light Client
There are three main kinds of node, with different trade-offs between disk space and how much they check for themselves.
Full Archival Node
A full archival node keeps every block on disk (roughly 800 GB in November 2026, growing about 80 GB a year) plus the data Bitcoin Core keeps alongside them, about 900 GB in all. It can send old blocks to other nodes and answer any question your wallets ask.
- Storage required: about 900 GB of disk today (blocks plus the data Bitcoin Core keeps alongside them), growing about 90 GB a year; buy a 2 TB drive
- Verification: complete; checks every transaction itself
- Network contribution: maximum; can serve every block to peers
- Best for: dedicated node hardware, and anyone who wants to connect wallets through an Electrum server (Lesson 4.7)
Pruned Node
A pruned node downloads and checks every block just like an archival node, then deletes old blocks to save space. Bitcoin Core can keep as little as 550 MB of blocks, but it also keeps the database of unspent coins it checks new transactions against, so a pruned node needs roughly 15–20 GB in total. A pruned node is just as secure: it has checked everything. But it has limits that matter for this course:
- Storage required: roughly 15–20 GB
- Verification: complete; same security as an archival node
- Network contribution: limited; can’t send old blocks to peers
- Limits: the Electrum servers that Lesson 4.7 uses to connect wallets such as Sparrow and BlueWallet, Electrs and Fulcrum, don’t work with a pruned node (Electrs, Fulcrum). A pruned node still downloads all ~800 GB once, and turning pruning off later means downloading the whole blockchain again.
- Best for: a laptop or desktop with little free space, where you use Bitcoin Core’s own wallet or a wallet that connects to Bitcoin Core directly
Light Client (SPV)
A light client, also called SPV (Simplified Payment Verification), doesn’t download or check the full blockchain. It downloads only block headers, the short summaries of each block, and asks full nodes for the transactions it cares about. It checks the proof of work in those headers and that each transaction is really in a block, but not whether it follows the rules; for that it trusts the miners. The nodes it asks can still hide transactions from it.
- Storage required: minimal
- Verification: partial; checks proof of work and inclusion, trusts miners for the rules
- Network contribution: none; it uses data from full nodes
- Best for: phone wallets and situations where running a full node isn’t possible
A newer kind of light client uses compact block filters (BIPs 157 and 158, often called Neutrino): full nodes send it a short summary of each block, it checks the summaries for its own addresses, and it downloads only the blocks that match. It doesn’t have to tell anyone which addresses are its own, which is better for privacy, but it still doesn’t check whether those transactions follow the rules; it trusts the miners for that. Zeus’s embedded LND node works this way; LDK Node, the built-in node new Zeus wallets use by default, asks an Esplora server about your addresses instead (Lesson 4.3).
In this course, “running a bitcoin node” means a full node, archival or pruned, that checks everything itself.
Hardware Requirements for Running a Bitcoin Node
You don’t need expensive hardware. Bitcoin is designed so that ordinary computers can check it.
Minimum Hardware
- Computer: a Raspberry Pi 5, or any small computer you can leave on. A Pi 4 works, but Umbrel now recommends the Pi 5 because USB drives “can make a Pi 4 crash”, and calls the Pi 4 “fine for tinkering” (Umbrel’s Raspberry Pi guide). For a node that will hold Lightning funds, choose a Pi 5 or a mini-PC.
- Storage: a 2 TB SSD. Besides the blocks, Bitcoin Core keeps undo data (what it needs to reverse a block if another chain wins) and its list of unspent coins, so it plans for about 900 GB of disk today (its built-in estimate, in version 32.1). A 1 TB drive is therefore already nearly full, and too small once you add an Electrum server’s index. Don’t use a mechanical hard drive: the first sync would take weeks instead of days.
- Internet: bitcoin.org asks for upload speeds of at least 400 kilobits per second. The first sync downloads about 800 GB; after that, downloads are around 20 GB a month, and “it’s common for full nodes on high-speed connections to use 200 gigabytes upload or more a month” (bitcoin.org). If your plan has a cap, Bitcoin Core’s
maxuploadtargetsetting limits uploads. - Power: a reliable supply (on a Pi, the official one). A small UPS, a battery that rides out short power cuts, protects the node from corruption when the power drops suddenly.
- MicroSD card or USB stick: on a Raspberry Pi, for the operating system. Check your platform’s guide: Umbrel recommends a microSD card of 32 GB or more, RaspiBlitz needs 64 GB or more, and myNode can also boot from a USB stick of 32 GB or more.
Recommended Hardware
For a smoother experience, especially if you plan to run Lightning too (Lesson 4.8):
- Computer: a small Intel or AMD mini-PC with 8 GB of memory or more
- Storage: a 2 TB NVMe SSD inside the machine, with room for the blockchain, an Electrum server and Lightning
- Internet: wired Ethernet rather than Wi-Fi
- Always on: run it 24/7, so your wallets can always reach it and your Lightning channels stay active
We don’t quote prices: they moved a lot in 2026, and Raspberry Pi raised board prices several times as memory got more expensive. Check current prices before you buy. For more on hardware, see our guide on running Bitcoin nodes at home.
Software Options for Your Bitcoin Node
Once you have the hardware, you need software. Either install Bitcoin Core directly, or use a node platform that packages everything with a friendly interface.
Bitcoin Core (Reference Implementation)
Bitcoin Core descends directly from Satoshi Nakamoto’s original software and is what most nodes run; it is often called the reference implementation. The current version is Bitcoin Core 32.1 (October 2026). Installing it yourself on Linux, macOS or Windows gives you the most control and needs some comfort with settings files or the command line.
Bitcoin Core includes a wallet, an interface other programs can use (JSON-RPC) and the peer-to-peer networking. Most node platforms run it underneath.
Node Distributions (Umbrel, Start9, RaspiBlitz, myNode)
Node distributions are ready-made operating systems that bundle Bitcoin Core with Lightning software (usually LND or Core Lightning), a web dashboard and extra apps. They make running a node as simple as possible.
- Umbrel: the most common choice for beginners, with a polished interface and an app store of hundreds of apps. Read our Umbrel review for 2026
- Start9 (StartOS): built around privacy and security, with Tor available as an optional service
- RaspiBlitz: community-built and designed for learning, with detailed documentation. See our RaspiBlitz setup tutorial
- myNode: a simpler option focused on Bitcoin and Lightning
The next lesson, Lesson 4.6: Umbrel vs Start9, compares them. Any of them will give you a working node; they differ mainly in ease of use, apps and privacy features.
The Privacy Argument for Running Your Own Node
Privacy is the reason many experienced Bitcoin users consider their own bitcoin node essential.
The Problem with Third-Party Nodes
Without your own node, your wallet has to ask a server about your balance and history, usually an Electrum server or the wallet company’s own service.
That server learns all your addresses and can link them together, because your wallet asked about all of them at once, from the same IP address. It knows your balance and when you received and spent. If the company keeps logs, it has a full picture of your Bitcoin activity.
This is true even with a self-custodial wallet. Self-custody stops the company from taking your bitcoin; it doesn’t stop it from seeing what you do.
How Your Own Node Fixes This
When your wallet uses your own node, its questions stay on your local network. Your node has the whole blockchain, so it can answer every question without asking anyone else.
Combining Your Node with Tor
Tor is a network that hides who is talking to whom. If your node talks to other nodes only through Tor, they can’t see your home IP address, so nobody watching the network can easily link your node, and the transactions it sends out, to where you live.
That “only” matters. Seeing Tor switched on doesn’t mean you are hidden: many setups use Tor alongside the ordinary internet (often called clearnet). On Umbrel, for example, the Bitcoin Node app makes outgoing connections over clearnet, Tor and I2P (another anonymity network) by default, and its “Make All Outgoing Connections to Clearnet Peers Over Tor” setting is off (Umbrel’s Bitcoin Node settings). With those defaults, clearnet peers still see your IP address, and your transactions can leave over clearnet. To be hidden, switch off clearnet connections or route them through Tor, in your platform’s peer settings.
There is also a middle option for your own transactions. Umbrel’s Privately Broadcast Transactions setting, available with Bitcoin Core 32.1 and off by default, sends the transactions that apps connected to your node submit out through Tor or I2P on short-lived connections, while other traffic can stay on clearnet. Bitcoin Core marks it as experimental.
The trade-offs: Tor is slower, which makes the first sync and some apps sluggish, and some services you may want to connect to only work over the ordinary internet. Many people use Tor for sending their own transactions and for reaching the node from outside the house. Our lesson on network privacy: Tor, VPNs and your own node compares the options in detail, and a node over Tor is a strong base for the other privacy techniques in Course 5, such as coin control and CoinJoin.
What Running a Node Won’t Do
Some common misunderstandings, so your expectations are right from the start.
It Won’t Mine Bitcoin
Running a node is not mining. Mining uses specialised machines (ASICs) that compute trillions of hashes per second to compete for block rewards. A node checks the miners’ work but doesn’t compete. You won’t earn block rewards or transaction fees.
It Won’t Earn You Money Directly
A full node has no built-in income. A Lightning node can earn small routing fees (Lesson 4.8), but a plain full node is a contribution, not a business. What you get is verification, privacy and independence.
It Won’t Make Transactions Faster
Miners confirm your transactions at the same speed whether or not you run a node. What you do get is seeing incoming transactions as soon as they reach your node’s mempool, and checking confirmations yourself.
It Won’t Protect You If Your Keys Are Compromised
A node checks the blockchain; it doesn’t guard your private keys. If someone gets your seed phrase, your node won’t stop them. You still need good key management, a hardware wallet and secure backups.
Key Takeaways
- Your own bitcoin node checks every transaction itself, the basis of “Don’t trust, verify”
- It protects your privacy only when your wallet is set to use it instead of a third-party server
- Nodes don’t vote: each one refuses blocks that break its rules, and the software you run decides which rules those are
- Plan for a 2 TB SSD: Bitcoin Core already needs about 900 GB of disk and grows about 90 GB a year, so a 1 TB drive is nearly full. A Raspberry Pi 5 or a mini-PC is enough
- A pruned node is just as secure but can’t run the Electrum servers most wallets use, and still downloads everything once
- Bitcoin Core doesn’t serve light wallets unless you turn that on
- Running a node doesn’t mine, earn money or speed up transactions: it gives you verification, privacy and independence
Frequently Asked Questions
How long does it take to sync a bitcoin node for the first time?
Roughly two to four days on a Raspberry Pi 5 with an SSD, longer on a Pi 4, and a day or two on a mini-PC with a fast NVMe drive. The drive’s speed and the computer’s memory matter most. A mechanical hard drive can take weeks. During the sync, your node downloads and checks the whole history since the genesis block.
Does running a bitcoin node cost a lot in electricity?
Usually not. Do the arithmetic for your own setup: a device that draws 10 watts around the clock uses about 88 kWh a year (10 W × 8,760 hours). At $0.20 per kWh, that is about $18 a year. Put in your own device’s power draw and your own electricity price; a cheap watt meter at the plug tells you the draw exactly.
Can I run a bitcoin node on my regular computer instead of dedicated hardware?
Yes. Bitcoin Core runs on Windows, macOS and Linux. The catch is uptime: if you turn the computer off often, the node has to catch up each time, and Lightning channels need a node that is always on. That’s why most people use a small dedicated machine.
Is running a bitcoin node legal?
In most countries, yes: a node checks and passes on public blockchain data, and doesn’t buy, sell or hold money for anyone. But “Bitcoin use is prohibited or restricted in some areas” (bitcoin.org), so check your local rules if you’re unsure. Also check your internet contract: some providers charge for heavy uploads.
Do I need technical knowledge to run a bitcoin node?
Very little, with a node platform like Umbrel or Start9. You write an image to a card, plug in the hardware and follow a setup page in your browser. If you can follow a recipe, you can set up a node. Lesson 4.7 walks through the whole process.
What happens if my node goes offline?
For a plain Bitcoin node, nothing bad: when it comes back, it downloads the blocks it missed. A Lightning node is different. If it stays offline too long, channel partners may force-close your channels, and nobody is watching for cheating attempts unless you use a watchtower (see our lesson on Lightning backups and watchtowers).
Check Your Understanding
1. You set up a node at home, but your phone wallet still uses its default server. Has your privacy improved?
Answer
No. The wallet still sends your addresses and IP address to the default server. Privacy only improves once the wallet is set to use your own node, usually through an Electrum server running on it (Lesson 4.7).
2. A friend wants to save money with a 1 TB drive and pruning. What do they give up?
Answer
Bitcoin Core already plans for about 900 GB of disk, so a 1 TB drive is nearly full today and too small once an Electrum server is added. Pruning would fix the space problem without weakening verification, but it stops Electrs and Fulcrum from working, so wallets like Sparrow or BlueWallet can’t use the node through them. The node still downloads all ~800 GB once, and switching pruning off later means downloading everything again.
3. A miner with most of the network’s hash power publishes a block paying itself 100 BTC. What does your node do?
Answer
It rejects the block, because it breaks the reward rule your node enforces. Mining power only decides between chains that are valid under your node’s rules; it can’t make an invalid block valid.