Bitcoin Addresses: What happens after 20 years?

[haploid23]

And how did you guys calculate these numbers? Is it how many possible combinations of all upper case letters, lower case letters, and numbers, with the possible 34 characters?

[DannyHamilton]

And how did you guys calculate these numbers? Is it how many possible combinations of all upper case letters, lower case letters, and numbers, with the possible 34 characters?

The bitcoin address is a base58 representation of a 160 bit hash value with a version number on the front and a 4 byte checksum on the end.

Since any given 160 bit hash will always have the same 4 bytes for the checksum, the checksum is not part of the calculation of how many distinct addresses there are.  Since we are specifically talking about 1 type of address, the version number is also not part of the calculation of how many distinct addresses there are.

The assumption everyone is making is that if you start with all possible 256 bit numbers (the ECDSA private key), and you calculate the ECDSA public keys (another set of 256 bit numbers), and you hash them with SHA256, and then hash the results of that with RIPEMD160, then you will have an even distribution across all 160 bit values.

Assuming that is true, then the total number of possible addresses is 2¹⁶⁰

Plug 2¹⁶⁰ into a calculator (or into the Google search box), and you'll find that the result is 1.4615016 X 10⁴⁸

[Plento]

There are this many addresses

1,461,501,637,330,902,918,203,684,832,716,283,019,655,932,542,976

Is that actually how many there are or did you pull that out of your behind?
If that's the number... wow.

[DannyHamilton]

There are this many addresses

1,461,501,637,330,902,918,203,684,832,716,283,019,655,932,542,976

Is that actually how many there are or did you pull that out of your behind?
If that's the number... wow.

That's the actual number (assuming that all possible 160 bit values will result from a SHA-256 hash followed by a RIPEMD-160 hash of all possible 256 bit ECDSA public keys using the Secp256k1 curve).

[RUEHL]

Long after man has fallen, future civilizations, possibly evolved from mice or cockroaches will still be generating Bitcoin addresses.

[ShakyhandsBTCer]

When you create an address nothing happens to the network. Only when payment is sent to that address is when the network will have a record of that address.

It would be possible, in theory (but extremely unlikely) for two people to "create" an address but neither send any BTC to it so neither would ever know that the other had created such address.

This does actually happen with brain wallet miners as they are "mining" the same kind of potential brain wallets.

[Skele]

The max amount of Bitcoin Addresses is more or less equal to the number of atoms that are in this world..

[silversurfer1958]

Save Bitcoin addresses, use mine instead 

[S4VV4S]

Save Bitcoin addresses, use mine instead 

For sure.
Give us your private key and we will do just that 

[icet208]

you will win many time at loto games before you run out of addresses.

[S4VV4S]

How does one even say this number: 1,461,501,637,330,902,918,203,684,832,716,283,019,655,932,542,976  

I bet it would be a whole paragraph  

[philipma1957]

All very interesting but here is a question how many addresses can be generated in a day one 1 fast pc?

 1 per second seems easy with a  code written for it.


 Lets say I want to possess all the address not used.  1 per second comes to 86,400 a day or  31,536,000 a year.

I also  say lets use a factor of 10   which means 315,360,000 a year    lets say everyone on the planet does that.

 10,000,000,000 is more then our real count of people but WTF   makes the math easy.


315,360,000  x 10,000,000,000 =   3,153,600,000,000,000,000   in one year    while a big number it is no where near the amount possible.  


3,153,600,000,000,000,000  is a lot smaller then 1,461,501,637,330,902,918,203,684,832,716,283,019,655,932,542,976



So even if people try to 'corner' the BTC address market it would take a long time to do so.

 And addresses could be increased in length  if really needed to do so.

[markj113]

Would it be possible for someone to write a malicious program to generate a massive amount of addresses continously?

I am thinking of a large botnet, all generating thousands of addresses a second?

[S4VV4S]

Would it be possible for someone to write a malicious program to generate a massive amount of addresses continously?

I am thinking of a large botnet, all generating thousands of addresses a second?

Good question.

What about Quantums.
Can they not generate thousands of addresses per second?

That could also be an attack on the network (of some sort).

[5flags]

Avram's law: As the length of a BitcoinTalk thread increases, the probability of a quantum computer being mentioned approaches 1.

[S4VV4S]

Avram's law: As the length of a BitcoinTalk thread increases, the probability of a quantum computer being mentioned approaches 1.

OK, your point being?

[5flags]

Avram's law: As the length of a BitcoinTalk thread increases, the probability of a quantum computer being mentioned approaches 1.

OK, your point being?

My point is that as the length of a BitcoinTalk thread increases, the probability of a quantum computer being mentioned approaches 1.

[S4VV4S]

Avram's law: As the length of a BitcoinTalk thread increases, the probability of a quantum computer being mentioned approaches 1.

OK, your point being?

My point is that as the length of a BitcoinTalk thread increases, the probability of a quantum computer being mentioned approaches 1.

For sure it does.
Even though Quantums right now cannot crack SHA-256 it still remains a thread.
Don't you think?

[Ekaros]

How many addresses does need to be generated to have 50% change for one clash?

I assume this is same problem as birthday paradox, just with very large numbers?

[Timmmaahh]

There are currently around 200.000 adresses in use:

https://blockchain.info/de/charts/n-unique-addresses

with a total of 2^160 is 1,461,501,637,330,902,918,203,684,832,716,283,019,655,932,542,976 possbile addresses.

soooooooooooooooooo

The chance to hit a address in use is about:

1.34*10^-43 %

0.000,000,000,000,000,000,000,000,000,000,000,000,000,013,4 %

pretty small number, huh ;-)