Maybe you have seen a Bitcoin address where the first letters are a word, similar like this:
1
fudCz15sHGR8L2YQnaG4JVMjMQpaDo37
1
BTCTUnYLskK7N9nXb17wf6oVYMYrX5WHG
1
DogemNVw8AZnMf3cB4L1wijGnr9DVKzia
1
Fomo7V86nWrjdv6JzU7yavtp5hfzZWsZr
1
NewbornSeatQVC9vegVHnxVseNAhhxewb
(1)Such addresses are vanity addresses and theoretically, it’s possible to generate every word with a few exceptions, but the number of the selected letters is limited. The reason is because you can use a tool and generate as many addresses as you like until you have found one with the desired combination of letters. The longer your prefix, the less likely a quick hit. Upper case letters are more likely to find than lower case letters. For example, the prefix 1Bitmover would take 2 months for 50% chance. The lower case 1bitmover is 58 times less likely.
(2)A few letters are excluded, because these are generally not part of Bitcoin addresses to avoid possible confusions:
l (letter lower L)
I (letter upper I)
O (letter upper O)
0 (number 0)
as well as all umlauts
There are several ways to generate a unique Bitcoin address. However, I recommend using the official version with vanitygen, uploaded by samr7 on Github. There are other ways offered on websites to create a vanity address, but I don’t recommend creating such an address on a website. If you create your address by a third party (the website), there is a possibility that someone can get access to your private keys. There have been problems in the past where bitcoins were stolen from such vanity addresses created on websites because
if someone knows your private key he has a chance to steal your Bitcoins from your wallet.
Therefore, please make sure to use the original version, which can be found on Github and you can run it without internet connection. Every website offering a service to create a vanity addresses without split key is dangerous.
That's how it works:
1. Download vanitygen:First you have to go to Github and download the original files from samr7, you can follow this link:
https://github.com/samr7/vanitygen/downloadsYou can download the latest version:
vanitygen-0.22-win.zip
2. Turn off internet connection while generating your Bitcoin addressIt’s also possible to create a vanity address when your internet connection is active, but for security reasons no internet connection is recommended. It would be even safer if you run the program on a computer that was never connected to the internet, but you can decide for yourself which security level is sufficient. It's always recommend to prefer high security standards to avoid any problems resulted by hacks because it's always possible that your device is compromised.
If you want maximal security you can generate your vanity address via
split-key.
3. Open the Command Prompt / PowerShellYou can start the Command Prompt by a right-click on the Windows icon in the lower left corner of your screen and select Command Prompt (Administrator) or simply using the key combination Windows + R
orif you do it like that you can skip #4 if you open the Command Prompt directly from where your vanity files are stored:
1. Go to the folder where vanitygen/oclvanitygen is stored.
2. Using Command Prompt: Press CTRL+SHIFT+Right Click on an empty space within the folder (not on the executable/files), click "Open command window here". Now the Command Prompt opens.
[1]2. Using Power Shell: Press SHIFT+Right Click on an empty space within the folder (not on the executable/files), click "Open PowerShell window here". Now PowerShell (Command Prompt) opens.
[2]3. You can start directly to enter the details you want, like described in step 5.
(source: nc50lc [1], nc50lc [2])
4. Enter pathsThis will open the Command Prompt window and start settings for the bitcoin address generation process.
The paths depend on where you have stored your vanitygen files. I have saved these on
C:\ in the folder
BTC, subfolder
vgen. I have to enter the following code to find the vanitygen.exe file:
C:\WINDOWS\system32>cd/
C:\ >cd/
BTC/
vgenC:\
BTC\
vgen>
vanitygen.exeFolder BTCSubfolder vgenFile name vanitygen.exeYou can try vanitygen.exe or use the file oclvanitygen.exe, it’s up to you which one you prefer. The difference between them is that vanitygen is CPU-based and oclvanitygen GPU-based. For our 4-digit combination, don’t matter if case-sensitive or case-insensitive, vanitygen is sufficient on a normal PC, oclvanitygen tends to be faster, if it works. For the technical background you'll find more information in the original article from 2011:
https://bitcointalksearch.org/topic/vanitygen-vanity-bitcoin-address-generatorminer-v022-25804.
Now this should look like this (with the corresponding paths where you have saved your subfolders and files):
When you have entered the file name of the
.exe file in the Command Prompt, press Enter.
5. Creation of the addressNow you see a list showing an overview of the available parameters to customize your address:
There are much more comments, if you have time you can try them but for our test a few commands are enough. As an example, I’ll show how to create a Bitcoin address with the first letters "test", everything written in lower case to generate a Bitcoin address that starts with
1test.
There are a few general things to keep in mind: the longer your prefix, the longer the search will take. This is not a problem with 4 digits, but it will take exponentially more time if there are more digits. In particular, if you want exactly the specified upper and lower case (case sensitive), the search takes longer than if upper and lower case would not matter (case insensitive).
If it’s ok for you to have mixed letters, both upper and lower case (TeSt, teST…), you can change it by adding the
-i (case insensitive) command.
To create the
1test address, we need the following commands:
-o C:\BTC\vgen\test.txt (saving the found private and public keys in a text file)
1test (your selected prefix)
Your command should look like this now:
C:\BTC\vgen>vanitygen.exe -o C:\BTC\vgen\test.txt 1test
If you are ready and have done the steps above, press Enter.
Now, the tool is searching for a public key with corresponding prefix (rate: 1.17 million keys per second). 50% in 2.4 minutes means your probability is 50% to find a public key with
1test in the next 2.4 minutes. The 5.1% is the probability of having found a hit in the already calculated keys so far.
If there is a hit, it will be shown and the search will be stopped. For the next time you can also add the comment
-k, to search for multiple hits until you close vanitygen.
Please also be careful and don't exaggerate it, if your PC or laptop may be overtaxed if the performance is not very high and may damage it. Our example of a 4-digit prefix should not be a problem, but with more digits difficulty will increase exponentially to find an address.
And surprise surprise, after a short time (around 2 minutes) vanitygen was successful and found an address:
1testgTQyiDMvtN67kj1w6R6J9dbo6bwd
and following associated private key:
5K9qCsz17Bd1UxtS7HQWc2rKz6ssNaBHMzK8pJvYiDGVYvUSEWg
The result is also stored as .txt file in our folder BTC:
Of course, I won’t use this
1test address because now everyone knows the private key and could steal Bitcoins from it. Therefore: don’t publish your private key anywhere.
6. Save your generated public and private keySecurity is always very important when it comes to Bitcoin. Keep your generated private key very safe, because it’s like the password to your Bitcoins. You can write it down on a sheet of paper, store it in a safe place and save it also on an USB stick that you only use for your private keys.
7. Done! Now, you have successfully created your own Bitcoin address. If you want to access it (like via Electrum) you can have a look
here. Make sure to test your address before you send large sums of Bitcoin to it. There is no way to figure out your private key afterwards if you have made a mistake.
In addition, I have created another vanity address, but I don’t tell you the private key:
1miau7e4tFSAGR4TkAJ8n32UMm2yLB9EH
If you like, you can post your customized vanity address here (but please
without private key if you are planning to use it).
© 1miau
11.01.2019
Additional links:
Security advice from LoyceVVanitygen: Vanity bitcoin address generator/miner release 2011 [v0.22]Rare address hall of fame
(1) generated by LoyceV(2) on hardware of LoyceV
Update 04/04/2019:
Member
Jean_Luc has developed another vanity-address-generator and published it on GitHub:
https://github.com/JeanLucPons/VanitySearchIt's much faster than vanitygen and supports besides P2PKH legacy addresses (1..) also SegWit addresses P2SH (3...) and bech32 (bc1q...).
You can check out his announcement on Bitcointalk here:
https://bitcointalksearch.org/topic/vanitysearch-yet-another-address-prefix-finder-5112311.
. I am still exploring new options..... 
