<p>The latest protocol version can be found by looking at the latest canonical Bitcoin client implementation source code currently v0.8.5 at <a href="https://github.com/bitcoin/bitcoin/blob/v0.8.5/src/version.h#L28" rel="nofollow">https://github.com/bitcoin/bitcoin/blob/v0.8.5/src/version.h#L28</a>. This should tally with what is described at <a href="https://en.bitcoin.it/wiki/Protocol_specification" rel="nofollow">https://en.bitcoin.it/wiki/Protocol_specification</a>.</p>

CC BY-SA 3.0
2013-10-02T12:34:50.027Z
2013-10-02T12:34:50.027Z
Dan
<p>As of october 2013, the protocol version is 70001. It's not linked anymore to client versions (so it doesn't correspond to version 0.7.0.1 in particular; 70001 was introduced in 0.8.0), and is intended to go up in increments of one, as changes specified in BIPs are implemented.</p>

CC BY-SA 3.0
2013-10-01T19:35:49.540Z
Thanks! How do you find this out? Is there a reason why it is not stated on the [Protocol specification](https://en.bitcoin.it/wiki/Protocol_specification)?
Dan
CC BY-SA 3.0
2013-10-01T22:22:22.300Z
Updating the specification on the wiki, and adding the protocol version in which every field was introduced would be an interesting project :)
Pieter Wuille
CC BY-SA 3.0
2013-10-01T23:31:43.433Z
All it needs is a sentence right at the top of the wiki page saying: 'The current protocol version is 70001.' Ideally it would also have a short description of the changes. I would update the wiki myself if I was allowed to edit it. Also where did you check to see what the current protocol version is and when it was updated?
Dan
CC BY-SA 3.0
2013-10-01T23:44:08.150Z
"current" protocol version... it's a bit more complex than that. Two clients negotiate which version to use when they connect; a few dozen versions numbers exist. It's not very useful to know what the latest protocol is without knowing what it entails. And I looked here: https://github.com/bitcoin/bitcoin/blob/v0.8.5/src/version.h#L28
Pieter Wuille
CC BY-SA 3.0
2013-10-02T12:29:55.033Z
Thanks for the help. I assumed the [https://en.bitcoin.it/wiki/Protocol_specification](Protocol specification) wiki page was designed to tell you what the protocol entails.
Dan
CC BY-SA 3.0
2013-10-01T19:26:24.493Z
2013-10-01T19:26:24.493Z
Pieter Wuille
<p>There's now a good overview at <a href="https://bitcoin.org/en/developer-reference#protocol-versions" rel="nofollow">https://bitcoin.org/en/developer-reference#protocol-versions</a>. The latest as of March 2014 is 70002.</p>

CC BY-SA 4.0
2021-12-17T02:16:58.893Z
This is actually out-dated. It's 70016
Melroy van den Berg
CC BY-SA 3.0
2015-05-27T17:59:01.527Z
2015-05-27T17:59:01.527Z
jwelsh
<p>How do I find out what version <a href="https://en.bitcoin.it/wiki/Protocol_specification#version" rel="noreferrer">Protocol specification</a> is describing?</p>

<development><protocol>
How do I find out what the latest protocol version is?
Dan
# How do I find out what the latest protocol version is?

(Asked by: username_0 on 2013-10-01)

How do I find out what version [Protocol specification](https://en.bitcoin.it/wiki/Protocol_specification#version) is describing?

**Tags:** development, protocol


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## 3 answers

### Answer by username_0 on 2013-10-02. Score: 0 | Accepted answer

The latest protocol version can be found by looking at the latest canonical Bitcoin client implementation source code currently v0.8.5 at <https://github.com/bitcoin/bitcoin/blob/v0.8.5/src/version.h#L28>. This should tally with what is described at <https://en.bitcoin.it/wiki/Protocol_specification>.


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### Answer by username_1 on 2013-10-01. Score: 6

As of october 2013, the protocol version is 70001. It's not linked anymore to client versions (so it doesn't correspond to version 0.7.0.1 in particular; 70001 was introduced in 0.8.0), and is intended to go up in increments of one, as changes specified in BIPs are implemented.

> **Comments:**
> **username_0**: Thanks! How do you find this out? Is there a reason why it is not stated on the [Protocol specification](https://en.bitcoin.it/wiki/Protocol_specification)?  
> **username_1**: Updating the specification on the wiki, and adding the protocol version in which every field was introduced would be an interesting project :)  
> **username_0**: All it needs is a sentence right at the top of the wiki page saying: 'The current protocol version is 70001.' Ideally it would also have a short description of the changes. I would update the wiki myself if I was allowed to edit it. Also where did you check to see what the current protocol version is and when it was updated?  
> **username_1**: "current" protocol version... it's a bit more complex than that. Two clients negotiate which version to use when they connect; a few dozen versions numbers exist. It's not very useful to know what the latest protocol is without knowing what it entails. And I looked here: https://github.com/bitcoin/bitcoin/blob/v0.8.5/src/version.h#L28  
> **username_0**: Thanks for the help. I assumed the [https://en.bitcoin.it/wiki/Protocol_specification](Protocol specification) wiki page was designed to tell you what the protocol entails.  

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### Answer by username_2 on 2015-05-27. Score: 1

There's now a good overview at <https://bitcoin.org/en/developer-reference#protocol-versions>. The latest as of March 2014 is 70002.

> **Comments:**
> **username_3**: This is actually out-dated. It's 70016  

---

