<p>The bitcoinj private keys are 32 bytes long. You would also want some sort of indexing around them so that you could access them efficiently.</p>

<p>If you used a deterministic wallet you would only need one seed and a chain code per customer and generate the addresses as required. I think they are typically 32 or 64 bytes long. </p>

CC BY-SA 3.0
2012-11-07T08:59:31.627Z
2012-11-07T09:06:50.743Z
2012-11-07T09:06:50.743Z
jim618
<p>Say for an exchange that manages thousands of users, and each transaction needs a new receiving address, how much space would thier wallet(s) take. </p>

<p>I am assuming 100000 users and each user would have about 10000 transactions, so there are about 10^9 keys to be stored. For safety, we would say there are 10^10 keys max that may be stored. </p>

<p>All I need to know is the size of one key stored in the wallet. </p>

CC BY-SA 3.0
2012-11-07T17:46:43.283Z
It will depend on which client (and version) you are referring to.  

The Bitcoin.org client will at some point (likely soon) be changing from wallet.dat (BDB) to some other storage method, which will impact the size of storage.
Stephen Gornick
CC BY-SA 3.0
2012-11-07T17:48:34.480Z
With the current Bitcoin.org client, you'll run into performance issues with a wallet that has many thousands of addresses long before storage space begins to be a concern.  That will be getting addressed with changes to the wallet database.
Stephen Gornick
<wallet>
How big can a wallet get?
Jus12
# How big can a wallet get?

(Asked by: username_0 on 2012-11-07)

Say for an exchange that manages thousands of users, and each transaction needs a new receiving address, how much space would thier wallet(s) take.

I am assuming 100000 users and each user would have about 10000 transactions, so there are about 10^9 keys to be stored. For safety, we would say there are 10^10 keys max that may be stored.

All I need to know is the size of one key stored in the wallet.

**Tags:** wallet

> **Comments:**
> **username_1**: It will depend on which client (and version) you are referring to.    The Bitcoin.org client will at some point (likely soon) be changing from wallet.dat (BDB) to some other storage method, which will impact the size of storage.  
> **username_1**: With the current Bitcoin.org client, you'll run into performance issues with a wallet that has many thousands of addresses long before storage space begins to be a concern.  That will be getting addressed with changes to the wallet database.  

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## 1 answers

### Answer by username_2 on 2012-11-07. Score: 3 | Accepted answer

The bitcoinj private keys are 32 bytes long. You would also want some sort of indexing around them so that you could access them efficiently.

If you used a deterministic wallet you would only need one seed and a chain code per customer and generate the addresses as required. I think they are typically 32 or 64 bytes long.


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