<p>This answer is now outdated please see <a href="https://bitcoin.stackexchange.com/a/38847/5651">Answer below</a></p>

<blockquote>
  <p>At this time, no, you can not strip the block chain (as far as I
  know). There is one programmer (Mark Freidenbach AKA maaku) who is
  working on further compressing the blockchain for the <a href="https://bitcoin.stackexchange.com/a/38847/5651">Satoshi bitcoin
  clients</a>.</p>
  
  <p>The entire block chain is currently needed to verify all coins are
  legitimate from the beginning of time. Plus there are coins in the
  older blocks that would not be included in new blocks, so some old
  miners might lose their coins.</p>
  
  <p><a href="https://bitcoin.stackexchange.com/a/38847/5651">1</a>: <a href="https://en.bitcoin.it/wiki/Original_Bitcoin_client" rel="nofollow noreferrer">https://en.bitcoin.it/wiki/Original_Bitcoin_client</a></p>
</blockquote>

CC BY-SA 3.0
2014-01-07T15:41:47.220Z
If I understand right, the entire block chain need merely be *processed* to verify coins. All that has to be *stored*, assuming you trust your storage, is the table of unused outputs & their corresponding values. (And of course all the text portions are highly compressible.) Am I incorrect?
Sai
CC BY-SA 3.0
2014-01-07T19:49:24.367Z
I misunderstood you a bit then, it might possible to do that but don't quote me on that one as I've never been able to successfully prune a block chain. I do not have as much experience with in depth blockchain surgery as some of the "older" coders do. Now, on the other hand it is possible to at very least prune the block coinbase block headers where you have messages from pools (like "Mined by AsicMiner" etc) that might save you some disk space.
Joe White
CC BY-SA 3.0
2014-01-07T19:52:11.300Z
have you considered getting a 64 gb thumb drive? They run about $25 usd each on amazon usa. you could always save the blockchain there
Joe White
CC BY-SA 3.0
2014-01-07T21:57:31.713Z
If I went that route, I'd probably use Armory's split online/offline mode and run the full chain on a server, which I can connect to occasionally via ssh-fs.
Sai
CC BY-SA 3.0
2015-07-28T09:20:16.900Z
This answer is now outdated.
Murch
CC BY-SA 3.0
2014-01-07T02:06:09.717Z
2016-02-28T14:47:38.390Z
2017-04-13T12:47:33.660Z
Joe White
<p>Since Bitcoin-Core 0.11.0 you can prune (trim) the blockchain in Bitcoin-Qt.
But not from the UI.
You need to add <code>prune=550</code> to your bitcoin.conf file and restart Bitcoin-Qt.</p>

<p><strong>Explanation:</strong>
<code>-prune=&lt;target in MiB&gt;</code> will tell bitcoin-core to remove blocks which are older than oldest block that can be kept with a chainsize (sum of block-sizes) of <code>&lt;target&gt;</code> (min. 550MiB as example above shows). A minimum of 550MiB ensures to keep at least 288 blocks (~2 days). 
<em>(simple explanation not including undo-data)</em></p>

<p><strong>Restriction:</strong>
<code>-prune</code> does disable all wallet functions in version 0.11 (will work with a wallet in version 0.12).</p>

CC BY-SA 3.0
2015-07-31T01:29:11.717Z
What are the tradeoffs here?
Michael Hampton
CC BY-SA 3.0
2015-07-31T06:05:12.180Z
You don't fully participate in the network health because you can't serve most historical blocks. Your node is considered to be a p2p leech. Along to this you can't use -txindex.
Jonas Schnelli
CC BY-SA 3.0
2015-07-31T08:42:37.330Z
I forgot to mention the biggest drawback with pruning in 0.11: it does *not* work with wallet enabled, though in upcoming version 0.12 it will also work with the wallet.
Jonas Schnelli
CC BY-SA 3.0
2015-07-31T09:06:48.050Z
I was under the impression that it did work, but that adding a private key to the wallet required a blockchain redownload.
Nick ODell
CC BY-SA 3.0
2015-07-31T09:51:37.643Z
Right. There are some restrictions with importing keys that can require a full reindex (=redownload of the blockchain). On a decent system with a fast internet connection this takes around 6h.
Jonas Schnelli
CC BY-SA 3.0
2015-10-12T02:23:05.587Z
The prune option is a command-line argument, not a bitcoin.conf setting.
Tim Sylvester
CC BY-SA 3.0
2015-10-12T07:34:03.253Z
@TimSylvester: not true. Command-line argument = bitcoin.conf.
Jonas Schnelli
CC BY-SA 3.0
2016-02-16T02:28:20.413Z
@JonasSchnelli is correct, wallet functions work in 0.12 with pruning.
mkabatek
CC BY-SA 3.0
2015-07-28T09:04:27.857Z
2017-09-04T19:27:44.443Z
2017-09-04T19:27:44.443Z
Jonas Schnelli
<p>If I recall it correctly, Ufasoft's multi-currency client stores the blockchain in a format of their own in which it gets compressed, so you might switch to it and see a small decrease in the usage of your hard-drive.</p>

<p>Be warned, though, there's no way to import the block-chain from bitcoin-qt's format to Usasoft, so the latter will have to re-download all the blocks from the very beginning.</p>

CC BY-SA 3.0
2014-01-07T15:44:08.823Z
AFAICT, only bitcoin-qt is interoperable w/ Armory, and I do want to have access to advanced features / good security. It's just the space limitation on my laptop that's a problem.
Sai
CC BY-SA 3.0
2014-01-07T16:45:58.540Z
You're right, Armory so far needs the original bitcoin-qt and can't operate with alternative clients. Too bad :(
Joe Pineda
CC BY-SA 3.0
2014-01-07T03:05:01.530Z
2014-01-07T03:05:01.530Z
Joe Pineda
<p>I run <a href="https://en.bitcoin.it/wiki/Bitcoin-Qt">Bitcoin-Qt</a> and <a href="https://bitcoinarmory.com/">Bitcoin Armory</a> on a laptop. I don't have the space to store the whole 20&nbsp;GB (or however big it is now) blockchain.</p>

<p>I understand the need to run through the entire thing for security, but I'd like it to only store relatively recent blocks + the summarized version (for example, the database of unused outputs / computed ledger). I'd like good security; I just don't have the space to store the whole thing.</p>

<p>Is there some way to configure Bitcoin-Qt / bitcoind to trim its data to a more reasonable size after it's gone through and processed the chain?</p>

<blockchain><bitcoind><bitcoin-core><storage-footprint><pruning>
Can Bitcoin-Qt be configured to trim the blockchain?
Sai
# Can Bitcoin-Qt be configured to trim the blockchain?

(Asked by: username_0 on 2014-01-06)

I run [Bitcoin-Qt](https://en.bitcoin.it/wiki/Bitcoin-Qt) and [Bitcoin Armory](https://bitcoinarmory.com/) on a laptop. I don't have the space to store the whole 20 GB (or however big it is now) blockchain.

I understand the need to run through the entire thing for security, but I'd like it to only store relatively recent blocks + the summarized version (for example, the database of unused outputs / computed ledger). I'd like good security; I just don't have the space to store the whole thing.

Is there some way to configure Bitcoin-Qt / bitcoind to trim its data to a more reasonable size after it's gone through and processed the chain?

**Tags:** blockchain, bitcoind, bitcoin-core, storage-footprint, pruning


---

## 3 answers

### Answer by username_1 on 2014-01-07. Score: 2 | Accepted answer

This answer is now outdated please see [Answer below](https://bitcoin.stackexchange.com/a/38847/5651)

> At this time, no, you can not strip the block chain (as far as I
> know). There is one programmer (Mark Freidenbach AKA maaku) who is
> working on further compressing the blockchain for the [Satoshi bitcoin
> clients](https://bitcoin.stackexchange.com/a/38847/5651).
>
> The entire block chain is currently needed to verify all coins are
> legitimate from the beginning of time. Plus there are coins in the
> older blocks that would not be included in new blocks, so some old
> miners might lose their coins.
>
> [1](https://bitcoin.stackexchange.com/a/38847/5651): <https://en.bitcoin.it/wiki/Original_Bitcoin_client>

> **Comments:**
> **username_0**: If I understand right, the entire block chain need merely be *processed* to verify coins. All that has to be *stored*, assuming you trust your storage, is the table of unused outputs & their corresponding values. (And of course all the text portions are highly compressible.) Am I incorrect?  
> **username_1**: I misunderstood you a bit then, it might possible to do that but don't quote me on that one as I've never been able to successfully prune a block chain. I do not have as much experience with in depth blockchain surgery as some of the "older" coders do. Now, on the other hand it is possible to at very least prune the block coinbase block headers where you have messages from pools (like "Mined by AsicMiner" etc) that might save you some disk space.  
> **username_1**: have you considered getting a 64 gb thumb drive? They run about $25 usd each on amazon usa. you could always save the blockchain there  
> **username_0**: If I went that route, I'd probably use Armory's split online/offline mode and run the full chain on a server, which I can connect to occasionally via ssh-fs.  
> **username_2**: This answer is now outdated.  

---

### Answer by username_3 on 2015-07-28. Score: 18

Since Bitcoin-Core 0.11.0 you can prune (trim) the blockchain in Bitcoin-Qt.
But not from the UI.
You need to add `prune=550` to your bitcoin.conf file and restart Bitcoin-Qt.

**Explanation:**
`-prune=<target in MiB>` will tell bitcoin-core to remove blocks which are older than oldest block that can be kept with a chainsize (sum of block-sizes) of `<target>` (min. 550MiB as example above shows). A minimum of 550MiB ensures to keep at least 288 blocks (~2 days).
*(simple explanation not including undo-data)*

**Restriction:**
`-prune` does disable all wallet functions in version 0.11 (will work with a wallet in version 0.12).

> **Comments:**
> **username_4**: What are the tradeoffs here?  
> **username_3**: You don't fully participate in the network health because you can't serve most historical blocks. Your node is considered to be a p2p leech. Along to this you can't use -txindex.  
> **username_3**: I forgot to mention the biggest drawback with pruning in 0.11: it does *not* work with wallet enabled, though in upcoming version 0.12 it will also work with the wallet.  
> **username_5**: I was under the impression that it did work, but that adding a private key to the wallet required a blockchain redownload.  
> **username_3**: Right. There are some restrictions with importing keys that can require a full reindex (=redownload of the blockchain). On a decent system with a fast internet connection this takes around 6h.  
> **username_6**: The prune option is a command-line argument, not a bitcoin.conf setting.  
> **username_3**: @username_6: not true. Command-line argument = bitcoin.conf.  
> **username_7**: @username_3 is correct, wallet functions work in 0.12 with pruning.  

---

### Answer by username_8 on 2014-01-07. Score: 0

If I recall it correctly, Ufasoft's multi-currency client stores the blockchain in a format of their own in which it gets compressed, so you might switch to it and see a small decrease in the usage of your hard-drive.

Be warned, though, there's no way to import the block-chain from bitcoin-qt's format to Usasoft, so the latter will have to re-download all the blocks from the very beginning.

> **Comments:**
> **username_0**: AFAICT, only bitcoin-qt is interoperable w/ Armory, and I do want to have access to advanced features / good security. It's just the space limitation on my laptop that's a problem.  
> **username_8**: You're right, Armory so far needs the original bitcoin-qt and can't operate with alternative clients. Too bad :(  

---

