<p>Technically, one block is enough. However, a single block orphan occurs with sufficient frequency that many Bitcoin business prefer three or six confirmations. The difference is more a matter of personal choice.</p>

<p>The hash rate of the network does not significantly impact the time between blocks because of the difficulty level. The difficulty level helps maintain the block timing at approximately every 10 minutes.</p>

<p><a href="http://bitcoin.org/chainfork.html" rel="nofollow">The 11/12 March 2013 blockchain fork</a> was a bit of a special case. Only <a href="https://bitcointalk.org/index.php?topic=152348" rel="nofollow">one known double spend occurred</a>, and that was a result of someone who crafted a raw transaction involving a company (OKpay) that did not heed the warning to cease transacting until the fork was resolved.</p>

CC BY-SA 3.0
2013-04-06T11:31:20.437Z
What is your source about this software company that crafted a raw transaction?
Shamoon
CC BY-SA 3.0
2013-04-07T16:31:46.577Z
It was not a software company, but an individual. I researched and found the story, and edited the answer above.
Colin Dean
CC BY-SA 3.0
2013-04-06T02:35:30.690Z
2013-04-07T16:32:20.580Z
2013-04-07T16:32:20.580Z
Colin Dean
<p>The point of waiting for six confirmations is that it becomes near impossible to create six blocks vs the network. So double spends a effectively eliminated.  With the hash rate of the network so high, is four blocks enough to have the same security? </p>

<p>Also, what about in the case of a fork like the one that resulted in 23 blocks?</p>

<blockchain><network><confirmations>
Is four confirmations enough if the network hash rate is so high?
Shamoon
# Is four confirmations enough if the network hash rate is so high?

(Asked by: username_0 on 2013-04-06)

The point of waiting for six confirmations is that it becomes near impossible to create six blocks vs the network. So double spends a effectively eliminated. With the hash rate of the network so high, is four blocks enough to have the same security?

Also, what about in the case of a fork like the one that resulted in 23 blocks?

**Tags:** blockchain, network, confirmations


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## 1 answers

### Answer by username_1 on 2013-04-06. Score: 2 | Accepted answer

Technically, one block is enough. However, a single block orphan occurs with sufficient frequency that many Bitcoin business prefer three or six confirmations. The difference is more a matter of personal choice.

The hash rate of the network does not significantly impact the time between blocks because of the difficulty level. The difficulty level helps maintain the block timing at approximately every 10 minutes.

[The 11/12 March 2013 blockchain fork](http://bitcoin.org/chainfork.html) was a bit of a special case. Only [one known double spend occurred](https://bitcointalk.org/index.php?topic=152348), and that was a result of someone who crafted a raw transaction involving a company (OKpay) that did not heed the warning to cease transacting until the fork was resolved.

> **Comments:**
> **username_0**: What is your source about this software company that crafted a raw transaction?  
> **username_1**: It was not a software company, but an individual. I researched and found the story, and edited the answer above.  

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