Why do people apparently "look up Bitcoin addresses on websites"?

Question

I often hear things such as:

Remember, if you look up an address on Blockchain.info or something, they will have a record of your IP address being interested in that address and thus associate it with you.

Sure. I follow that logic. But what I don't understand is why they would do that in the first place. Why use some "website" when the whole point is that Bitcoin is decentralized and you have your own wallet/client/node that you can look at?

And what is their "objective" with inspecting some address that they have just used? Why not look in Bitcoin Core (or whatever they use) to simply see if it's in memory pool or has confirmations or whatever it is they are trying to look up?

Answer 1

@Prince M's answer is great, I have just a couple things to add:

Wallet software will generally only show you transactions relevant to the wallet, so if you ever want to explore transactions beyond your own, you might want to use a block explorer to do so.

If you are running a full node, then you can look up transactions using bitcoin-cli, but a full node does not index the blockchain according to addresses, and so the intuitive way to explore transactions that most block explorer services provide does not really exist when using software like bitcoin-core. Likewise 'address balances' are not explicitly retrievable from a full node, though there do exist some open-source self-hosted blockchain explorers that you can run on top of a node, that will compute and display such things for you. But in any case, simply running a full node does not lay open the blockchain for you in a human-digestible format, getting to that point requires additional work and software.

On another note, some wallets don't have very informative user interfaces. For example, I've seen wallets which do not display the fee-rate your transaction includes, and so if you're waiting for confirmation, just looking at your wallet will not provide any information about where in the mempool your transaction resides. Looking up the transaction using a block explorer may be helpful to the user in this case.

Of course, this can be tragic, as using such an online block explorer service can be detrimental to your privacy. For this reason, I would recommend using a block explorer that offers a .onion domain, so that you can view it over the tor network, to help preserve your privacy.

Answer 2

Let me preface by saying I am not an expert. There are a lot of experts active in this community, so you will hopefully get a more holistic answer from a more knowledgeable user. I can answer your question with my personal experience however, because I do look at those websites!

Why use some "website" when the whole point is that Bitcoin is decentralized and you have your own wallet/client/node that you can look at?

I use blockchain blockexplorer and blockstream block explorer several times a day as an easy and quick way to cross analyze and verify things I am learning about related to bitcoin. As I learn new concepts regarding addresses, transaction weight, segwit, PKskript, sigscript, etc, I can go look at transactions or blocks to help confirm my understanding, and using those sites is easy because someone has already organized the information contained in the transactions and blocks into easily human readable format. It is also fun to look through historical blocks to verify where "halving" took place, or special transactions like the transaction puzzles I posted about the other day. Sometimes I just watch block explorer for fun, look for patterns or observations.

And what is their "objective" with inspecting some address that they have just used? Why not look in Bitcoin Core (or whatever they use)

I don't typically look for my own transactions (I've made very few). I already described above why I look on these websites, and for those reasons I wouldn't care at all if my IP address was linked to those transactions (because the ones I click on are more-or-less random). It is probably true that I could do all of the functions I described above by running a full node and running the queries myself, but there are some obvious reasons why myself and other probably don't. The minimum requirements for running a full node are not terrible, but are more than my computer can handle. Also, the average person is not always savvy enough with programming to navigate bitcoin core to verify their own transactions. Most people are probably not even savvy enough to cooperate in bitcoin transactions let alone verify their own.

In general I would say you are right, the general mood among bitcoin enthusiasts seems to be "don't trust, verify". But there are also probably a lot of people scanning explorer websites like me just for fun - and a lot of people checking transactions that don't have the skills to verify themselves, or simply just don't care if their IP address is connected to that transaction.

plot twist Also, if lots of people like me click on random transactions on the block explorers, then their will be lots of IP addresses associated to a given transaction!