how to make custom address without private key ?

[Anillos2]

I always found the idea of black holes or coin-eating addresses interesting. I know they have been used in 'legit' or 'useful' purposed as a proof-of-burn to issue an altcoin, but the mere act of sending BTC to such an address always reminds me of the Joker!

Proof of burn is like a lottery ticket, because you can burn lots of coins for nothing if you don't have luck.

[1715079080]

1715079080

[1715079080]

1715079080

[coinpr0n]

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If it's using sha256x2 for checksum confirmation, is it difficult for address generator to guess checksum ?
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I don't understand the question.

A checksum isn't "guessed", it is calculated.

You start with the 160 bit hash value that you want, then you add the one byte version number to the beginning, then you calculate the sha256 hash of the resulting 21 bytes, then you calculate the sha256 hash of the resulting 32 bytes.  The first 4 bytes of the resulting 32 bytes is the checksum.  No need to "guess" anything.

Cool. That was a clear way of explaining it. I totally got the concept now and it makes a lot of sense.

[mlferro]

https://blockchain.info/address/1BitcoinEaterAddressDontSendf59kuE (3 BTC)

The address above currently holds 1.95690423 BTC, what a pity... that amount can save many people from hunger

really could  yes. And surely leave many boys (who nothing to eat) very happy.

[takas]

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If it's using sha256x2 for checksum confirmation, is it difficult for address generator to guess checksum ?
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I don't understand the question.

A checksum isn't "guessed", it is calculated.

You start with the 160 bit hash value that you want, then you add the one byte version number to the beginning, then you calculate the sha256 hash of the resulting 21 bytes, then you calculate the sha256 hash of the resulting 32 bytes.  The first 4 bytes of the resulting 32 bytes is the checksum.  No need to "guess" anything.

So in order to create custom address such as 1CUSTOMADDRESSXXX... , randomly generate addresses and find the matched one is only way.

[DannyHamilton]

So in order to create custom address such as 1CUSTOMADDRESSXXX... , randomly generate addresses and find the matched one is only way.

That depends.

If you want an address that can receive bitcoins, but nobody will ever be able to spend any of those bitcoins at all, then you can start with the characters that you want "CUSTOMADDRESSXXX...", put a 1 in front of it, and calculate the checksum.

Voila, you have a valid bitcoin address, and any bitcoins sent to the address are permanently unspendable.


If you want an address that can receive bitcoins, and you want to be able to spend the bitcoins that are received at that address, then you must randomly generate addresses from private keys and compare the resulting addresses to the string that you want until you get lucky and stumble across an address with a string you want.

Voila, you have a valid bitcoin address, and you can spend the bitcoins received at the address.

Note:  It is impossible to create your example address.  The letter O is not a valid bitcoin base58 character.  If you use the number 0 instead of the letter O, then the resulting address would be valid: CUST0MADDRESSXXX...

[Drakebill]

why would anyone want to make such address. there are lots of good things u CA do with spare cash u don't need.

[takas]

So in order to create custom address such as 1CUSTOMADDRESSXXX... , randomly generate addresses and find the matched one is only way.

That depends.

If you want an address that can receive bitcoins, but nobody will ever be able to spend any of those bitcoins at all, then you can start with the characters that you want "CUSTOMADDRESSXXX...", put a 1 in front of it, and calculate the checksum.

Voila, you have a valid bitcoin address, and any bitcoins sent to the address are permanently unspendable.


If you want an address that can receive bitcoins, and you want to be able to spend the bitcoins that are received at that address, then you must randomly generate addresses from private keys and compare the resulting addresses to the string that you want until you get lucky and stumble across an address with a string you want.

Voila, you have a valid bitcoin address, and you can spend the bitcoins received at the address.

Note:  It is impossible to create your example address.  The letter O is not a valid bitcoin base58 character.  If you use the number 0 instead of the letter O, then the resulting address would be valid: CUST0MADDRESSXXX...

Thank you, I understand crearly, and I have made!