1
There have been estimates of the number of published addresses. For example:
https://blockchain.info/charts/n-unique-addresses
(this chart seems to be underestimating the address count)
However, I'm interested in the number of public keys. Most of them would be obtained from transaction inputs containing P2PKH response scripts.
This article suggests there are at least 56 million, but doesn't describe how this number was found or if the raw data are available:
... I obtained around 56 million pubkeys from the blockchain (mid-January) [2015] ...
Is there a convenient source that gives the number of published public keys in real time?
2We've had a similar question recently and if memory serves (I'll find the link) the only way to do this is to parse the Blockchain data using a library like Python-bitcoinrpc in conjunction with a full node of bitcoincore – Wizard Of Ozzie – 2015-06-03T04:16:50.647
2
@WizardOfOzzie: I think you might be talking about Extract all public keys from blockchain
– Murch – 2015-06-03T11:27:57.263The concept of "number of unique keys" (that article) is different from "number of published keys" - I can't really tell from your question which you are after. Seems like the latter. Can you please clarify? – SDsolar – 2017-12-04T03:36:26.807