Author

Topic: bitcoin address generated so far vs total address ever (Read 1497 times)

sr. member
Activity: 427
Merit: 250
Even if you generate all addresses, to run out of addresses, all of them must have to be used simultaneously, which is pretty much impossible.
legendary
Activity: 2198
Merit: 1014
Franko is Freedom
Such huge numbers to even be able to possibly grasp.
sr. member
Activity: 467
Merit: 267
You have a probability of having a collision of two addresses greater than 50% at around the square root.
So at around 2^80 addresses, there is a 1/2 chance of having two people generating the same address.
2^80 ~ 10^24. It's still a gigantic number.
DrG
legendary
Activity: 2086
Merit: 1035
And long time before we reach 1/2 of all addresses it fails because when there is a chance that you get a key that already been taken, it fails. Luckily we ain't reach that far as previous post says Smiley

A long time before we reach that point humans and machines will probably have melded and we could upload our digital signature to the cloud - that would be our own biometric key.

Statistically the solar system is more likely to get destroyed than the chance of grabbing somebody's stash.
legendary
Activity: 1974
Merit: 1029
And long time before we reach 1/2 of all addresses it fails because when there is a chance that you get a key that already been taken, it fails. Luckily we ain't reach that far as previous post says Smiley

At most 21 quadrillion addresses can have some balance in them. What you describe is picking up an address that has had some balance in the past, not that currently has it.
legendary
Activity: 2170
Merit: 1427
how long will it take to run out of all possible keys?

If a billion people each continuously generate a billion keys per second, it will take 46,343,913,000,000,000,000,000 years to generate all possible keys.

It is estimated that the solar system is only 4,600,000,000 years old.

It is estimated that the sun will last less than 10,000,000,000 more years, and that it will destroy the earth billions of years before that.

I think we have more pressing issues to worry about than the number of keys that have been used.

Atleast it's good to know how many years we still can generate btc addresses  Grin
full member
Activity: 157
Merit: 100
And long time before we reach 1/2 of all addresses it fails because when there is a chance that you get a key that already been taken, it fails. Luckily we ain't reach that far as previous post says Smiley

Nothing will fail when "you get a key that already been taken".
The problem will be that you will be able to spend what's already there, to the detriment of the "existing owner".
member
Activity: 92
Merit: 10
And long time before we reach 1/2 of all addresses it fails because when there is a chance that you get a key that already been taken, it fails. Luckily we ain't reach that far as previous post says Smiley
legendary
Activity: 3472
Merit: 4801
how long will it take to run out of all possible keys?

If a billion people each continuously generate a billion keys per second, it will take 46,343,913,000,000,000,000,000 years to generate all possible keys.

It is estimated that the solar system is only 4,600,000,000 years old.

It is estimated that the sun will last less than 10,000,000,000 more years, and that it will destroy the earth billions of years before that.

I think we have more pressing issues to worry about than the number of keys that have been used.
sr. member
Activity: 448
Merit: 250
If I remember, ripemd160 is the limiting factor so there are 2^160 possible public addresses.

For private keys, 2^256 is often cited but it is actually slightly smaller, some in the top of range are not used by the ECC algorithm bitcoin uses.

But it doesn't matter because 2^160 is smaller, so there are going to be collisions where two different private keys produce the same public address.
I doubt we'll ever find one, but they have to exist. Mapping a larger set to a smaller set guarantees they exist.

So 2^160 is how many addresses are available.

Yup I forgot about ripemd160 2^160 or 16^40 = 1.4615016373309029182036848327163e+48

Still a very large number.
vip
Activity: 1428
Merit: 1145
Quote
So 2^160 is how many addresses are available.

Or 1.4615016e+48, which is the same for...

full member
Activity: 168
Merit: 100
If I remember, ripemd160 is the limiting factor so there are 2^160 possible public addresses.

For private keys, 2^256 is often cited but it is actually slightly smaller, some in the top of range are not used by the ECC algorithm bitcoin uses.

But it doesn't matter because 2^160 is smaller, so there are going to be collisions where two different private keys produce the same public address.
I doubt we'll ever find one, but they have to exist. Mapping a larger set to a smaller set guarantees they exist.

So 2^160 is how many addresses are available.
sr. member
Activity: 448
Merit: 250
what is the total number of private keys that can ever be generated and what percentage of keys has been generated as of now..

how long will it take to run out of all possible keys?

Deep question there. I remember reading somewhere that it would take millions of years to run out of bitcoin addresses. Would anyone like to clarify/expand on this? I too would like to hear a more simple/explaining answer.

Having just imported the blockchain into a Mysql DB I see a total of 42,150,031 (as of block 311761) public key hashes and total amount of address out there I believe are 16^160 or 4.5624406176221952186411716057003e+192

The 42.1M number are only addresses that sent or received bitcoin so far, it is not a reflection of all addresses that have been generated.

So it will be a while before we run out.
hero member
Activity: 588
Merit: 500
Get ready for PrimeDice Sig Campaign!
Deep question there. I remember reading somewhere that it would take millions of years to run out of bitcoin addresses. Would anyone like to clarify/expand on this? I too would like to hear a more simple/explaining answer.
hero member
Activity: 756
Merit: 502
what is the total number of private keys that can ever be generated and what percentage of keys has been generated as of now..

how long will it take to run out of all possible keys?
Jump to: