Custom Bitcoin address ?

[Bitcoin Magazine]

by hack, I meant how likely is someone to find the correct private key given the public key with that generator

If you mean, how likely is it that someone could generate a private key that matches an already existing and in-use bitcoin address that has funds in it, then the answer is:

Astronomically small, so small that there probably isn't enough energy in the known universe to power the hardware needed to do it.

what if you are just powering 1 desktop computer that exists in parallel realities
where each reality is working on a different [quantum] exponent

[grifferz]

Astronomically small, so small that there probably isn't enough energy in the known universe to power the hardware needed to do it.

lol.

it's just that here https://en.bitcoin.it/wiki/Vanitygen

they is it took 10 seconds to generate this key pair...

To generate one specific key pair out of the countless billions that also start with "1Boat".

so if I try to generate an address with that smame prefix, woulnd't i get the same private key?

You'd get a different one that also starts with "1Boat".

If you don't believe me, please do tell it that you want to generate the key pair that starts with "1BoatSLRHtKNngkdXEeobR76b53LETtpyT" i.e. the whole exact key with the same case, and tell us how long it thinks it will need in order to do this.

[unick]

I will try for sure... out of curiosity.

Like I said, it made me wonder

but it makes sense, there is a LOT of possible keys that start with 1Boat and has 34 characters ! It all comes down to entropy

[TookDk]

I will try for sure... out of curiosity.

Like I said, it made me wonder but it makes sense, there is a LOT of possible keys that start with 1Boat and has 34 characters !

Greater probability of all the oxygen molecules in the room your are sitting will go to the ceiling at the same time and you will suffocate as a result, then you finding that exact key.

[sssubito]

I will try for sure... out of curiosity.

Don't waste your time...

My GPU crunches about 15.3 MKeys/s with oclvanitygen, everything longer than 1BoatSLRHtKNngkdXEeobR76b53 was rejected as too long (I had to cut away the last seven chars) and 1BoatSLRHtKNngkdXEeobR76b53 alone is about to take ~4.021*10^30 years for 50% probability to find a match. And that's not even guaranteed ... 

The probability to find the private key for a given Bitcoin address is mathematically not zero, but as said before, there is not enough energy and maybe time in the universe to succeed such an attempt.

[TookDk]

2^160 is such an unbelievable large number.

There are more oxygen molecules on the earth than 2^160.

It would be the same, as someone tags one single oxygen molecules, at a random time and place -  and then after search through all the oxygen molecules on the earth until you find the one that is tagged.

[Light]

Now would be a good time for someone to post that infographic about how the laws of physics mean that it's really impossible to brute force private keys.

Anyways, I wouldn't bother wasting your time trying to find and exact match - realistically your more likely to win the lottery 5 times in a row. If your going to mine for an address just for yourself use either oclvanitygen or vanitygen depending in whether you wish to use your GPU or CpU. Do note that your GPU in most cases is faster.

Finally, even if a site uses split key generation I still wouldn't use them, it's still far safer to generate the private key on an air gapped PC.

[bountygiver]

by hack, I meant how likely is someone to find the correct private key given the public key with that generator

If you mean, how likely is it that someone could generate a private key that matches an already existing and in-use bitcoin address that has funds in it, then the answer is:

Astronomically small, so small that there probably isn't enough energy in the known universe to power the hardware needed to do it.

There is enough energy in the universe to power that.

The correction should be "There is not enough human accessible energy to crack them at the current level of technology (and for the next few decades or even centuries)"

[Light]

There is enough energy in the universe to power that.

The correction should be "There is not enough human accessible energy to crack them at the current level of technology (and for the next few decades or even centuries)"

Actually, no. I'm going to give you this overly used infographic.


The problem comes from possible incorrect implementation of the various cryptographic primatives, or quantum computers breaking the algorithm itself rather than a bruteforce attack on every single known key. The chance of a collision is so low I'd say you'd be more likely to be able to win the lottery 5 times in a row than this occurring.