Please please
please do not do this. The cryptosystem which Bitcoin keys and addresses are part of assumes for its security that its private keys are uniformly random numbers. Flipping coins by hand will definitely not give uniformly random numbers, and is probably so biased (depending on your hand, the coin, what side you pick it up from, the surface it lands on, etc, etc) that you can measure it yourself by just flipping a coin and counting the zeroes and ones.
If you swap out one component of a cryptosystem for another you have constructed a new cryptosystem and need to argue its security. And I guarantee you won't find a good security argument for "Bitcoin script with biased randomness".
To add to the presumption of insecurity that should be applied to all new cryptosystems, let me point out that much of this one is gibberish:
Step by Step Tutorial- Create a Bitcoin address by flipping a coin
- Create a Bitcoin address so secret, {Insert name of your Government Spy agency Here} wont even know who made it!
Linkage between addresses and identities has nothing to do with key generation. This sort of linkage is done by exploiting ordinary address mismanagement.
Simple Intro
A Bitcoin private key is a really big number that is created in a very specific format.
A Bitcoin private key is an integer modulo the field order of the secp256k1 curvegroup used by Bitcoin's signature scheme. It is an element of an additive group and has no size.
Once the private key is created, it can then be pushed through a mathematical gauntlet and produce a Public Address that anyone can freely give out without fear.
Publishing your addresses is a (potentially very serious) privacy risk and cannot be done "freely without fear".
Every Public Address corresponds to exactly one Private Key and vice-versa.
This is simply false.
If you could guess a private key, you could access and spend the Bitcoins stored at the address as if they were yours. It is not likely that you or anyone else will ever guess a private key.
"not likely" is an understatement. The probability is 2^{-160}. There is nothing in yourordinary life that is comparable to this number. Nobody, ever, will ever find a private key by guessing uniformly at random. (Of course, they may exploit biases in random number generators and guess nonuniformly at random; this has happened many times.)
You can however, create you own private keys from scratch or you can let the wallet do it for you. Your option.
This is horrifically bad advice. Key management is hard enough to do when using software specifically designed to do it for you. Manual key management is stupid, and manual key
generation is even stupider.
How to create a Bitcoin Private Key and therefore a Unique Public Address, by flipping a Coin.
Get a coin. Label one side as “1” and the other side as “0”
Flip the coin a minimum of 256 times and record the results as you go in groups of 4. When you are done, your binary sequence should look something like this:
Binary: (Below is four sequences of 64 bits each 4x64=256)
0010 1000 1000 1111 0011 1001 1011 1011 1111 1101 0011 0110
1101 1010 0101 1010
0001 0010 1101 0001 0110 0010 1100 1011 0001 1000 1001 0111
1100 1001 0000 0010
0010 1000 1000 1011 0011 1001 1011 1011 0011 0110 1101 1010
0101 1010 0001 0010
1101 0001 0110 0010 1100 1011 0001 1000 1001 0111 1100 1001
0000 0010 0011 1101
The number of flips equals the bitness of the encryption.
This statement is nonsensical. Besides, there is no encryption in Bitcoin.
256 flips = 256 bit encryption. The grouping and spaces are not important. They are grouped this way to make them "Human Friendly."
The next step is to convert the Binary to HEX. Finding a Binary to Hex converter on-line that will handle that sized number is no easy task.
http://www.mathsisfun.com/binary-decimal-hexadecimal-converter.html – This one can handle 64 bits at a time. Just keep them in order and separate. Do 64 bits at a time. (4 times)
Every part of this tells me you should not be touching encoding or decoding systems, let alone cryptosystems. Please do not give cryptographic advice if you do not know what you are talking about. It is dangerous and therefore immoral. Do you also advise people how to do surgery on themselves and others? Do you tell them how to pilot aircraft? (Perhaps you are an expert on one or both of these things; then how would you like to see laymen giving such advice?)
The Binary Number above Converted to HEX: (32 bytes)
288F 39BB FD36 DA5A 12D1 62CB 1897 C902 288B 39BB 36DA 5A12 D162 CB18 97C9 023D
This HEX number is your Raw Private Key, and again the spacing is not important.
Next, Cut and paste the HEX number into
https://brainwallet.github.io/#converter and choose “HEX” to “B58Check.” This will create a very large number that begins with a “5”. This number is your private key “Wallet Import Format”.
Please don't advise people to use brainwallet. About half of the things on that site are implemented dangerously; I have good reason to believe this is deliberate because its creator it attempting to steal money from users of its compromised keys. One good reason is that none of the dangerous things are labeled as such (or better, removed) despite repeated admonishment from myself and others.
*** You cannot use the Brainwallet BIN to HEX converter due to the fact that Brianwallet adds a “0” place holder to every 4 bit sequence. e.g. “1111” converted to HEX is “F” but Brainwallet converts it as “0F” ***
The HEX above converted to B58Check WIF:
5J89cr5WGdvQWeeekN5ZGzuXVsWREbAYku6MDeUgrJTjX1ZHhCX
Next copy the private key WIF code. Click “Generator” and paste the private key into the Private Key box. This will create your new Public Address.
WIF Format above Converted to Bitcoin Public Address:
1Cwd7i5R6GM56njNhyyr7RRUYo6e1AMg9A
You have now created a Private Bitcoin Key and a Public Address from 256 coin flips!
As I mentioned above, manual key management is stupid and dangerous. (I'm going to get a lot of flack from paper wallet users for this claim. Nonetheless I stand by it.)
EXTRA SECURITY: Just in case you are worried about using the online generator, you can download the .zip file at the bottom of the page (off Brainwallet) and set the generator up on your computer. You can run this program off-line with no Internet connection for extra security.
This provides no extra security. Can you clarify (for my understanding of psychology) why you would think it does?
This is unbelievably bad advice. If you are being paid to do this, then I advise you to speak with a priest and take a serious look at the moral decisions you are making. In any case, please stop.
EXTRA COINS: The Brainwallet site is also set up to do 25 other coins in addition to Bitcoin.
I'll just leave this here.I'm going to stop now; the remainder was simply instructions on importing keys, and I've already discussed manual key management. I will also say, without justification (as I'm tired of repeating it, not because I have none) that web wallets, and blockchain.info in particular, are not a safe way to store Bitcoin keys, and I strongly advise anyone storing coins with such a service to move them out of there immediately.