Bitcoin Forum

Can a bitcoin address can be recovered from public key... If not so how is it related to bitcoin address???

No way to do that.
You can only brute force, but that's useless, it would take literally forever to get the private key that matches the public key.
The concept is this: https://en.wikipedia.org/wiki/Public-key_cryptography

This would kind of defeat the security of Bitcoin

Then how did this guy Evil-Knievel in this thread https://bitcointalk.org/index.php?topic=421842.60 (https://bitcointalk.org/index.php?topic=421842.60) cracked an address with his script which he calls "horseshit" :D

Its not impossible, its just very very low probability

I was shocked to see a private key coming outta public key..... Dnt know what he did but it certainly seems bitcoin encryption things are loose....

He bruteforced it and got lucky, probablity of bruteforcing a private key is: 2 to the power of -124 if I am correct. At any rate, if you do not know about encryption of bitcoin, better not to make FUD statements. And well who knows it was his own address and he made it seem as if he cracked bitcoin encryption.

Yeah it maybe.... Lol he is selling that horseshit for 2 btc damn.... Nice try scammer "Evil-Kenevil"

No.

https://www.youtube.com/watch?v=ZloHVKk7DHk

nope if it was possible then nobody's bitcoin would be safe, but if you are talking about HD wallets im pretty sure you can get the addresses from the Xpub key

Are you saying hd wallets like multibit HD WALLETS etc or like this...??

It seems that those replying so far do not understand the difference between a public and a private key.

The answer is *of course* a Bitcoin address can be determined from a public key as it is basically just a base58 formatted version of a cryptographic hash of the public key.

What you can't do is go from the Bitcoin address back to the public key (as cryptographic hashes are not reversible) and the public key of course can't be used to do anything like a tx without also having the private key (which cannot be determined from it).

This might be related to the risk of Quantum computers breaking ECDSA. However, one should not worry much about this. If we come to the point where it is risky, we're probably going to change the algorithm to something better. People need to stop living in the far future (cause of fear), and start living in the present.

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Who and when? Links please.

This is the link https://bitcointalk.org/index.php?topic=421842.60 a guy name evil-kenevel cracked a private key outta public key and address

all cracked "experimentation" are from a knowed private and public key.
 ::) it's more easy when you know the direction ...

in real world, use the email to spam with porn ad derived with key map spyware ... and you have the wallet file send via dropbox (retrieved by the spyware).

You can't recover bitcoins using public key as the name suggest it's a public key and you are allowed to share it with anyone...But every bitcoin address do have private key too which is required to recover your wallet and address and without it you can't recover yoir account..you can't just guess the private key and brute forcing is next to impossible because private key is very long in length..

This[1] was so painfull to read, but to see the replies just continue...

Edit:

This is a public key: 0489AD08CA699563497B8F92AFE2252CBCBD5B2381C9E9E64C716B144BEE44B6E4B756B7AD5A17B 21E4D707694D182802A6C1285343C9BE48543F7FCEF54B7128D
There are two possible addresses for this.


This is how you get from the one to the other:

https://en.bitcoin.it/w/images/en/9/9b/PubKeyToAddr.png

What you need to spend is the private(!) key.


[1] The rest of the thread not your reply.

So thats why brainwallet is closed permanently for these security issues...

hmmm.. that certainly answers my question...thanxxx your replies were worthy for me ..thnx for sharing some knowledge :P  ;)

i dont think so that you can recover your bitcoin address from your public key, their is security options and 2fa security with this you can recover your bitcoin address.

Crackning a private key.... against the Universe, Satoshi and Bitcoin. Whichever tools you find, they will be all fake.

i really doubt that it is possible at least not with the computers that we have nowadays if we would be able to do that wouldnt bitcoins be not safe?

^^

This.

One of the reasons bitcoin is such a pioneering invention/discovery is because of it's unique security features. Bitcoin would be pointless if you could easily crack a wallets contents by using the public key.

In theory no, because the odds of collision would be the same as an meteor destroy earth in the next seconds.

But if your random number generator is broken, maybe

Holy hell, will people please read replies before adding to the mess?

Short answer: Yes, of course a bitcoin address can be recovered from a public key. 

Longer answer: See replies by pjsonowal.

No it is not. A public key can not be reverse engineered back to its privkey and you cannot actually recover a privkey using bruteforce. It is a mess but if you put information like that, you will just cause confusion, and thus, a mess.

Most bitcoin users never need to worry about publickey. 

Yes it is - do you understand that the question does not mention "private key" but instead "public key" or did you simply not read it?


Unfortunately it is you (and most other posters in this topic) that are causing the mess and confusion by not even bothering to read the OP.

To the @OP - unfortunately this is why this forum is no longer very useful for any sort of technical advice. :(

Yes, it can be. Try reading some posts before you and the question in OP.

As for Evil-Knievel, I've seen him plenty of times here in this forum conducting bounties for certain projects related to bitcoin's cryptography. On the linked thread, he attacked the weak addresses present on the curve, but I'll doubt that he would continue on doing that and actually break the code.

thats impossible ,as i read on blockchain TOS (CMIIW) , if you lose your address and forgot to backup , than you lose your money

no wa,public key as i know just can move some bitcoin from other wallet.

Can we rename the thread wall of shame please?

Looks like you are the only one to actually read the question indeed.

I think people just automatically assume private key whenever someone starts talking about recovering something from an address.

Nope, brainwallet is known not only for their possible lapse in human mind but also the insecure algorithm used to generate them. There was recently a hacking tool (http://www.coindesk.com/new-cracking-tool-exposes-major-flaw-in-bitcoin-brainwallets/) that was revealed and it could potentially cause people to lose money.

https://elmiqueblog.files.wordpress.com/2009/11/neo.jpg

Only he can.

Only Chuck Norris can, and I tell you, he just need to blink once to find the private key!
But returning on the natural world: Only if you can win 3 max prize lotteries in a row you can find it.

Talking about chances:

Finding the same bitcoin address (with private key) = 1 in 2^160

Compare to: [BAD THINGS]
1. Being killed by a vending machine. (1 in 112 million)
2. Being killed in a terrorist attack on an airline. (1 in 25 million)
3. Dying from a bee, hornet or wasp sting. (1 in 6.1 million)
4. Dying from being left-handed and using a right-handed product incorrectly. (1 in 4.4 million)
5. Dying in a plane crash. (1 in 1 million)
6. Being killed by flesh-eating bacteria. (1 in 1 million)
7. Getting Struck by Lightning. (1 in 1 million)
8. Drowning (1 in 2,000,000)
9. Drowning specifically in a bathtub. (1 in 840,000)
10. Dying in an on-the-job accident. (1 in 48,000)
11. Being murdered…just in general. (1 in 18,000)

Compare to: [GOOD THINGS]
1. Having identical quadruplets. (1 in 15 million)
2. Becoming US president. (1 in 10 million)
3. Becoming a Movie Star. (1 in 1,505,000)
4. Becoming an astronaut. (1 in 12,100,000)
5. Getting a royal flush in a first hand of poker. (1 in 649,740)
6. Winning an Olympic gold medal. (1 in 662,000)
7. Becoming a pro athlete. (1 in 22,000)
8. Winning an academy award. (1 in 11,500)
8. Finding out your child is a genius. (1 to 250)
9. Dating a millionaire. (1 to 215)

HOWEVER, the chance of finding the same bitcoin address (with private key) is still higher than the chance that YOU exist:

http://mmb-s3.s3.amazonaws.com/2014/07/what-are-the-odds-ig.jpg

So, there is still a chance!!!

Guys the things are now messing up here...

i asked only the question that CAN A BITCOIN ADDRESS CAN BE RECOVERED FROM PUBLIC KEY??

and i got the answer - "NO"

reason:-https://www.comodo.com/resources/small-business/digital-certificates2.php (https://www.comodo.com/resources/small-business/digital-certificates2.php)

there is only two-three points that can recover your address:-
1) private key
2) mnemonic
3) email address and phone no. that was linked to the address(if you had made via blockchain)

and talking about evil-kennevel guy, i think it was his own address and he made it seem like other account.

IF NOT I CHALLENGE HIM TO CRACK MY ADDY.

Your question is misleading. Normally the public key is the address. And for full access, to spend the funds, you need the private key.

Now, you forgot about "vanity generator" which in theory can give you the private key of a bitcoin address you want (or at least based on a pattern).
But you will not live long enough for that to come out from vanity gen.

As somebody said, only Chuck Norris can help, since he already counted to infinite and back, twice :)

Just lock the thread. You will only get more answers from people that do not even bother reading your question properly.


and I thought we have been over this.


Has nothing to do with bitcoin.


Private key -> pubkey -> address


That only works for HD wallets and

mnemonic -> master private key -> private key -> pubkey -> address


Thats service specific and has nothing to do with the inner workings of bitcoin.

As long as someone does not have a weak R value cough blockchain tinkering with code.
If I recall correctly there was an exploit that was patched similar to that in the area of address reuse
https://en.bitcoin.it/wiki/Address_reuse
https://bitcointalk.org/index.php?topic=581411.0

Simple Answer: NO

http://thumbnails.visually.netdna-cdn.com/bitcoin-infographic_5029189c9cbaf.jpg

Did you even look at the picture you posted? OP is talking about the public key.

Are you guys done bashing? You cannot recover an address from another Bitcoin address. The whole process need to go back to the privkey, hence the comment of me and other users.

"That" is what was asked "Can you recover address from address" in broken English and that is the proper answer.

Even a botnet would not be powerful enough to crack private keys.

Skipping the physics and doing back-of-the-envelope math ...

There are 2¹⁶⁰ addresses. Just to count up to 2¹⁵⁹ (half the possible keys) would consume at least 4.8x10²⁵ joules. The energy consumption of the entire world is 5.6x10¹⁰ joules.

TL;DR Using all the electricity generated by the entire world, it would take 10¹⁵ (1,000,000,000,000,000) years to just to count through half the possible keys.

As a couple people have mentioned, a poorly-chosen private key can be recovered. This includes some brain wallets and bugs in private key generation. Anybody claiming to be able to recover any private key is lying or he would have done so with any number of multi-million dollar addresses readily available in the blockchain.

Not unless quantum computers (even just a few) have taken off. Until then, no.

And even if quantum computers take off soon, there are mathematically proven ways to protect data even from them...but not the current form of BTC keys (or SSL, TLS, PGP, etc.). Still, that's a long way off by most estimates. And they would go after much, much bigger targets than a BTC wallet.

So, no.

just hope that quantum computer would be revealed to the public first, otherwise they can break ecdsa easily, and determinate public key from address

for the op this can be useful https://en.bitcoin.it/wiki/Technical_background_of_version_1_Bitcoin_addresses


this is a public key, with a quantum computer you can easily determinate it form an address

and sha256 is impossible to crack for now, even satoshi said that there is a possibility in the future that something unknown could break it

like quantum computer could pose a serious threat, surely not something which i call impossible

It's in the picture did you read each part of the process ?
And the infographic shows the process it merited posting.

Op's question was
Can a bitcoin address can be recovered from public key... If not so how is it related to bitcoin address???

The answer is NO
However you can try  if your looking for an atom in the sun or run a defective client.
(you cannot compute the public key without the private key).  A problem is that if one private key is leaked the others can easily be computed, but there is no general way to avoid it. )

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Since that does not happen in most use cases the simple answer is NO

It explains how a TX is created and confirmed, it does not explain how addresses are created.


Your answer is wrong, same as 90% of others here that have no idea what they are talking about. The address is the hash the of public key. Of course anyone can hash the public key in the correct way and get the address. Thus the address can be "recovered" from the public key.

What you are possibly refering to is the private key. The chain goes one way like this:

private key -> public key -> address

not (!) the other way around

address -\> public key -\> private key

but thats not the question asked by OP.

I see what you meant there made an error, but the info-graphic still is handy.
It took me a while there to get the question misread it your right the private key comes first the bitcoin address comes last not that the bitcoin address is deduced backwards to find the master public key then the private key.

Was thinking of a strange configuration where the master public key reveals a private key through a hash in a deterministic wallet exploit.
https://bitcoinmagazine.com/articles/deterministic-wallets-advantages-flaw-1385450276
https://en.bitcoin.it/wiki/BIP_0032

Posting the proper one:

https://en.bitcoin.it/w/images/en/9/9b/PubKeyToAddr.png



In that case, I am confused (!) Following the Process it is Private -> Public -> Address
EDIT: Read it as no its the other way around nvm your fine.

How to create Bitcoin Address
https://en.bitcoin.it/wiki/Technical_background_of_version_1_Bitcoin_addresses

0 - Having a private ECDSA key

   18E14A7B6A307F426A94F8114701E7C8E774E7F9A47E2C2035DB29A206321725

1 - Take the corresponding public key generated with it (65 bytes, 1 byte 0x04, 32 bytes corresponding to X coordinate, 32 bytes corresponding to Y coordinate)

   0450863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B23522CD470243453A 299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6

2 - Perform SHA-256 hashing on the public key

   600FFE422B4E00731A59557A5CCA46CC183944191006324A447BDB2D98D4B408

3 - Perform RIPEMD-160 hashing on the result of SHA-256

   010966776006953D5567439E5E39F86A0D273BEE

4 - Add version byte in front of RIPEMD-160 hash (0x00 for Main Network)

   00010966776006953D5567439E5E39F86A0D273BEE

(note that below steps are the Base58Check encoding, which has multiple library options available implementing it)
5 - Perform SHA-256 hash on the extended RIPEMD-160 result

   445C7A8007A93D8733188288BB320A8FE2DEBD2AE1B47F0F50BC10BAE845C094

6 - Perform SHA-256 hash on the result of the previous SHA-256 hash

   D61967F63C7DD183914A4AE452C9F6AD5D462CE3D277798075B107615C1A8A30

7 - Take the first 4 bytes of the second SHA-256 hash. This is the address checksum

   D61967F6

8 - Add the 4 checksum bytes from stage 7 at the end of extended RIPEMD-160 hash from stage 4. This is the 25-byte binary Bitcoin Address.

   00010966776006953D5567439E5E39F86A0D273BEED61967F6

9 - Convert the result from a byte string into a base58 string using Base58Check encoding. This is the most commonly used Bitcoin Address format

   16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM

http://security.stackexchange.com/questions/54136/possible-to-derive-private-key-from-public-key-given-enough-computing-power

Bitcoin address is Base58 encoded a hash of public key. So if you have a public key you can calculate bitcoin address ;-)
But you will not be able spend bitcoins - you will need a private key  :P

Guys Thanks for your replies....it helped me a lot !!!!!

SO I AM LOCKING THIS TOPIC....

THANK YOU AGAIN!!!!  :)