<p>Ah, not surprisingly, it's in the block's "version" field. It looks like core blocks are versioned as "v4", while "classic" blocks are versioned as "v805306368" and "<a href="https://github.com/bitcoin/bips/blob/master/bip-0109.mediawiki" rel="nofollow">BIP109</a>".</p>

CC BY-SA 3.0
2016-03-12T16:19:45.553Z
2016-03-12T16:19:45.553Z
redsquirrel
<p>Sites like <a href="http://xtnodes.com/" rel="nofollow">http://xtnodes.com/</a> are tracking which versions of Bitcoin software are being used to create blocks. Where are they looking in the block structure to determine which software version generated the block?</p>

<block><bitcoin-classic>
How can you tell a block is Classic vs Core?
redsquirrel
# How can you tell a block is Classic vs Core?

(Asked by: username_0 on 2016-03-12)

Sites like <http://xtnodes.com/> are tracking which versions of Bitcoin software are being used to create blocks. Where are they looking in the block structure to determine which software version generated the block?

**Tags:** block, bitcoin-classic


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## 1 answers

### Answer by username_0 on 2016-03-12. Score: 1

Ah, not surprisingly, it's in the block's "version" field. It looks like core blocks are versioned as "v4", while "classic" blocks are versioned as "v805306368" and "[BIP109](https://github.com/bitcoin/bips/blob/master/bip-0109.mediawiki)".


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