> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/bitcoin/bitcoin/llms.txt
> Use this file to discover all available pages before exploring further.

# Running a Pruned Node

> Reduce disk space requirements by enabling block pruning in Bitcoin Core

Pruning allows Bitcoin Core to delete old block data after validation, significantly reducing disk space requirements while maintaining a fully validating node.

## What is Pruning?

A pruned node:

* ✅ **Downloads and validates** the entire blockchain
* ✅ **Maintains** the full UTXO set for validation
* ✅ **Enforces** all consensus rules
* ❌ **Cannot serve** historical blocks to other nodes
* ❌ **Cannot rescan** the blockchain for old wallet transactions

<Info>
  Pruned nodes are still fully validating nodes. They verify every transaction and block but don't store all historical data.
</Info>

## Storage Requirements

### Full Node vs Pruned Node

| Node Type              | Disk Space Required                 |
| ---------------------- | ----------------------------------- |
| Full node              | \~600 GB (growing \~50-100 GB/year) |
| Pruned node (550 MB)   | \~10 GB                             |
| Pruned node (5000 MB)  | \~15 GB                             |
| Pruned node (10000 MB) | \~20 GB                             |

<Tip>
  The actual disk usage will be slightly larger than your prune target due to the UTXO database, chainstate, and other necessary data.
</Tip>

## Enabling Pruning

### Manual Pruning

Enable manual pruning without automatic deletion:

```bash theme={null}
bitcoind -prune=1
```

With manual pruning:

* Blocks are not automatically deleted
* Use the `pruneblockchain` RPC to delete specific blocks
* Gives you control over when and what to prune

```bash theme={null}
# Prune blocks up to height 800000
bitcoin-cli pruneblockchain 800000

# Prune automatically to stay under target
bitcoin-cli pruneblockchain
```

### Automatic Pruning

Set a target disk usage in MiB:

```bash theme={null}
# Keep approximately 10 GB of blocks
bitcoind -prune=10000

# Minimum: 550 MB
bitcoind -prune=550
```

<Warning>
  The minimum prune setting is 550 MiB. Bitcoin Core needs to retain at least this much block data to function properly.
</Warning>

### In bitcoin.conf

To make pruning permanent, add to your `bitcoin.conf` file:

```ini theme={null}
# Automatic pruning with ~10 GB target
prune=10000
```

<Steps>
  <Step title="Stop Bitcoin Core">
    ```bash theme={null}
    bitcoin-cli stop
    ```
  </Step>

  <Step title="Edit bitcoin.conf">
    Add the prune setting to your configuration file:

    ```bash theme={null}
    echo "prune=10000" >> ~/.bitcoin/bitcoin.conf
    ```
  </Step>

  <Step title="Restart Bitcoin Core">
    ```bash theme={null}
    bitcoind -daemon
    ```
  </Step>
</Steps>

## Enabling Pruning on an Existing Node

<Warning>
  **Important**: Enabling pruning requires re-downloading and re-validating the entire blockchain.

  If you already have a full node and want to enable pruning:

  1. Stop Bitcoin Core
  2. Enable pruning in configuration
  3. Bitcoin Core will automatically prune during the next startup

  **Disabling pruning** also requires re-downloading the entire blockchain to restore historical blocks.
</Warning>

There is one exception: if your existing node is fully synced, you can enable pruning and it will start pruning old blocks without re-downloading:

```bash theme={null}
bitcoin-cli stop
# Add prune=10000 to bitcoin.conf
bitcoind -daemon
```

Bitcoin Core will prune old blocks to reach your target size.

## How Pruning Works

### During Initial Block Download

<Steps>
  <Step title="Download blocks">
    Bitcoin Core downloads blocks from peers normally.
  </Step>

  <Step title="Validate blocks">
    Each block is fully validated according to consensus rules.
  </Step>

  <Step title="Update UTXO set">
    The UTXO database is updated with new unspent outputs.
  </Step>

  <Step title="Prune old blocks">
    Once validation is complete and the prune target is exceeded, old blocks are deleted.

    Bitcoin Core retains recent blocks for serving to peers and reorg protection.
  </Step>
</Steps>

### After IBD

Once synchronized:

* New blocks are validated and added normally
* Old blocks are automatically pruned to maintain the target size
* The most recent blocks are always retained (at least one week's worth)

<Info>
  Pruned nodes keep the most recent blocks to help the network and protect against chain reorganizations.
</Info>

## Limitations of Pruned Nodes

### Cannot Serve Historical Blocks

Pruned nodes cannot:

* Help new nodes with initial block download for old blocks
* Serve historical blocks to other peers
* Participate fully in the archival node network

They can still:

* Serve recent blocks to peers
* Relay transactions and new blocks
* Fully validate the blockchain

### Incompatible with Transaction Index

Pruning is incompatible with `-txindex`:

```bash theme={null}
# This will fail
bitcoind -prune=1000 -txindex
```

<Warning>
  You cannot enable transaction indexing (`-txindex`) on a pruned node. The transaction index requires access to all historical blocks.
</Warning>

### Limited Wallet Rescanning

Pruned nodes can only rescan the blockchain from the oldest retained block:

```bash theme={null}
# This may fail if blocks are pruned
bitcoin-cli rescanblockchain 0
```

```json theme={null}
{
  "error": "Cannot rescan beyond pruned blocks. Use -reindex"
}
```

To rescan from genesis, you would need to re-download the blockchain.

## Pruning with Assumeutxo

When using assumeutxo with a pruned node:

* The minimum `-prune` setting is 550 MiB normally
* With assumeutxo, at least 1100 MiB is used temporarily
* Two chainstates exist during background sync

<Warning>
  When using assumeutxo with `-prune`, the prune budget may be exceeded temporarily. Ensure you have extra disk space available during the background sync.
</Warning>

## Pruning During IBD

Bitcoin Core prunes more aggressively during initial block download:

* Prunes 10% extra to avoid pruning again immediately
* Reduces I/O operations during sync
* Helps IBD complete faster on pruned nodes

```bash theme={null}
# Start a fresh pruned node
bitcoind -prune=10000 -dbcache=4096
```

<Tip>
  Combine pruning with a large `-dbcache` for faster IBD on systems with limited disk space but adequate RAM.
</Tip>

## Checking Prune Status

Verify pruning is enabled:

```bash theme={null}
bitcoin-cli getblockchaininfo
```

```json theme={null}
{
  "pruned": true,
  "pruneheight": 780000,
  "automatic_pruning": true,
  "prune_target_size": 10485760000
}
```

* **pruned**: Whether pruning is enabled
* **pruneheight**: Oldest block still available
* **automatic\_pruning**: If automatic pruning is active
* **prune\_target\_size**: Target size in bytes

## Best Practices

### Choosing a Prune Target

* **Minimum (550 MB)**: For extremely constrained systems
* **1-5 GB**: Reasonable for most VPS or embedded systems
* **10+ GB**: Allows serving more blocks to peers
* **No pruning**: If you have the disk space, run a full node

### Considerations

1. **Wallet usage**: If you frequently import old addresses or keys, consider a larger target or full node
2. **Network contribution**: Larger prune targets help the network more
3. **Available space**: Always leave extra space beyond your target
4. **Future growth**: Blockchain grows \~50-100 GB per year

<Tip>
  If unsure, start with `-prune=10000` (10 GB). You can always adjust later, though it requires re-syncing.
</Tip>

## Converting Between Pruned and Full

### Full Node → Pruned Node

```bash theme={null}
bitcoin-cli stop
# Add prune=10000 to bitcoin.conf  
bitcoind -daemon
```

Bitcoin Core will prune existing blocks to reach the target.

### Pruned Node → Full Node

<Warning>
  Reverting from pruned to full node requires re-downloading the entire blockchain.
</Warning>

```bash theme={null}
bitcoin-cli stop
# Remove or comment out prune= from bitcoin.conf
bitcoind -reindex
```

The `-reindex` will not restore pruned blocks. You need to re-download:

```bash theme={null}
# Delete blockchain data (keep wallet!)
rm -rf ~/.bitcoin/blocks ~/.bitcoin/chainstate

# Restart without pruning
bitcoind -daemon
```

## Next Steps

<CardGroup cols={2}>
  <Card title="Performance Optimization" icon="gauge-high" href="/operations/performance-optimization">
    Further optimize your pruned node
  </Card>

  <Card title="Reduce Traffic" icon="download" href="/operations/performance-optimization#reducing-network-traffic">
    Minimize bandwidth usage
  </Card>

  <Card title="Initial Block Download" icon="download" href="/operations/initial-block-download">
    Optimize IBD for pruned nodes
  </Card>

  <Card title="Configuration" icon="sliders" href="/configuration/bitcoin-conf">
    Learn about other configuration options
  </Card>
</CardGroup>