Video - Bitcoin 101 - Fun with Brain Wallets Making and Playing With Them - Bitcoin Security

There's no idea in Bitcoin more science fiction ready than the idea of brain wallets. To actually hold your wealth inside your head (and no where else) is something that can be done only with bitcoins. In this video we set up and play with a number of brain wallets (of course they aren't really brain wallets if we tell everyone the passwords and private keys...but you get the idea). Whether you are a fiction writer or an escaping refugee, this video is for you.


Hello! This is James D'Angelo and welcome to the Bitcoin 101 Blackboard Series.

A few years ago, there was an Italian man driving up to Switzerland with his family in his car and the authorities stopped the car because it was seeming to hang a little bit too low. After a big search where they finally started to pull out the seat panels, he found a lot of gold hidden under there, and the man was trying to move his wealth out of Italy for various reasons.

Now, most people could come up with a number of other ways to do this, but one of the most outrageous and sci-fi ways that he might have been able to do this is to use this thing known as a brain wallet. A brain wallet is the only way that's ever been conceived of storing all your value, all your worth, just in your head such that if you were shot no one would be able to recover the value anywhere.

So a brain wallet is really just your ability to store your private key in some way that you could retrieve it through something that you have memorized.

Now the strings of a regular private key which start with a five and have an enormous number of digits after it, are not really well made for memorizing. Okay. They go on for characters what, sixty-four characters long. And are the same length of any SHA-256 code. Well, because of the same length of SHA-256, these private keys can be generated by just using a SHA-256. And this is really the secret behind doing a brain wallet. Okay.

The SHA-256 is as we've talked about many times a hash function. And this hash function takes any input at all, be it the US Constitution or your name and churns it out like hashing, like hash rounds or hashing me where the name comes from into this one string that’s 64 characters long. Okay. We're going to play around with that but that is the essence behind making a brain wallet.

Now, you can go online and find out lots of warnings and scares and things you should do when you're creating a brain wallet, and I highly recommend looking through this page on the Bitcoin Wiki called Brain Wallet. They give you some examples here. They give you some big warm things that you want to follow, right, especially if you're looking to put a lot of wealth into your brain wallet.

But let's go ahead and make one. And our first one, this is going to be really simply we just go to any SHA-256 calculator that you find online and anything that you put in there can be the basis for your brain wallet. So I'll come up with something that's very easy for me to memorize. Happy New Year. And now I can calculate the SHA-256 hash and that can now be the private key for a Bitcoin wallet.

Now, it's not a very safe one because a lot of people can come up with Happy New Year and every time you put Happy New Year into a hash function you will come up with the same thing. And just to explore that, let's go to this other great address. And we've updated it recently so and I actually like it better. Where when you're actually going on you have to move your mouse around to create randomness. And it takes a bunch of points of randomness, all these points on the screen and uses that to seed this random number that it might use to generate a brand new Bitcoin account.

Now we're not going to be using this feature and get address right now. But it's just good to know about it and what it's doing. You can even type letters in here whatever. Okay. And this is just a randomly generated address. So here's your private key and here's your public address. So let's open that up a little bit. But I can go back to my Happy New Year and I can copy this SHA hash which can be considered a private key to a Bitcoin wallet and I can pop that in here into the wallet details enter private key.

Let's do that. View details. Well, this is my public address for my new brain wallet, my Happy New Year. I don't think I'm going to forget that right. So this is an address and I can actually start sending money to that public address but if anyone gets ahold of either this big long string down here in yellow which is the private key or even Happy New Year and decides to churn it through the SHA-256 hash which is what everyone does well, they'll be able to take your money out of your brain wallet. And let's just play around with that. We can take Happy New Year and we can stuff that into the brain wallet feature.

So if you go to, one of the best websites, one of the most reliable websites in the Bitcoin community. There's single wallet, paper wallet, bulk wall and we've spoken about a few of these and we've used wallet details. This time we're talking about brain wallet and we're going to say let's show it and we put in our Happy New Year and then we hit view. My passphrase I entered is too short. Well, they're actually trying to protect me from putting something in but if I put it -- was able to put it in it would have given me the same private key as this.

Now let's create a more secure brain wallet. And what they recommend here on the Bitcoin wiki is doing something that's long and unusual. So their example is man made it to the moon and decided it stink like yellow cheese. Okay. And they made a number of misspellings and things with cheeses misspelled. Man made it to the moon with two commas and decide it stink like yellow cheese. Well, this is much more memorable than sort of any big SHA-256 string right here. But it turns out for Bitcoin it's really the same. As long as you remember to plug it through the SHA-256 this right here should generate that string below. Let's try it out. All right. We copy that without the quotes and we go to our online SHA-256 calculator, paste that and now hit calculate SHA hash. And indeed, that number down there is the same one, seven four E eight six and the ending with a B nine is the same one that they've got here.

Now we can take that number, this big SHA-256 hash and we can stuff that into our private key over here in wallet details. And view details and we get this address, one C-E-U-9-U-G and indeed that's the exact same one that they're using in the example. Now a big note about passwords. So if you're going to create your own brain wallet you'll see that is pretty snooty. They don't want you to put in a short passcode and it turns out that even the best invented short pass code, right, word like Stephen fifty-six exclamation point, that's nowhere near as good a password as the expression that they use. So the longer and weirder the better.

And in fact, every character that you add to your password increases the randomness, increases the difficulty of calculating that password. So these traditional sort of online banking passwords are really terrible crappy passwords. It's not as big a deal that you're using exclamation points as you're just making it long and weird.

So let's come up with one of our own. And maybe we'll even send some money to it. So let's go over here to our online SHA-256 hash calculator and let's do something that most people might even guess, World Bitcoin Network. Now that's a pretty weak passphrase. But let's send some money to it. So we've got to find the SHA hash which is this A21 character. Then we go to, wallet details and we pop in our private key, view details. So this is the public address for the brain wallet world bitcoin network and I can send money to that. So let's do that. Let's send some money to a Coinbase. Okay. Let's go to my wallet here.

Here we are at Coinbase and I'm going to send money to my brain wallet World Bitcoin Network. So let's send a dollar. And likely within minutes after posting this video someone will pull it out and we'll just leave a message. I don't know. Terrible brain wallet. And we press send. And then we could even go see it on and we go down here, it's a little fine and we put in the address and we hit search. There I have sent money from Coinbase and the money goes straight to my World Bitcoin Network brain wallet, 98 cent.

So it's really there on the blockchain and what's going to happen is soon after seeing this video people are going to take that off. And so really what this page is it's just the history of this address and you can see that that's the first transaction ever made with it. Let's play around with brain wallet just a little bit further because there's some curious things in the world of brain wallets, right.

One interesting thing is if you type in such Satoshi Nakamoto, you know, capital letters at the beginning and you calculate the hash. Well, that gives you this hash right here, you take that hash. Once again you go to and you see what that corresponds to because that's your private key in terms of Bitcoin addresses. There is Jay Try and it turns out if you type this into, someone's actually use that address before. So this is the Satoshi Nakamoto brain wallet, right. And it corresponds to this address and we can see that it's received a total of 23 cents. But it's got some very peculiar transactions here. So a lot of people been playing around with the idea of brain wallets. And just for fun, right now the final balance is zero we could go in and send it a little bit. Okay. So let's send it a little bit. Send, let's send 30 cents. And you can go pull that out as well, send money. This transaction requires a bit of a little fee, why not. Let's put a little fee. The miners will get to gobble that up and we send the money.

And usually the smaller transactions on Coinbase get the fees. Boom! So we sent it to an external account. So let's have a little bit more fun. Let's try and make a good brain wallet. We showed you a lot of bad examples let's make a very good example. So we could use World Bitcoin Network and then the more we add the better the brain wallet will be. James was here on a sunny day eating lasagna and then we could make that a certain number of A's. That now you've increased your quality dramatically of your passphrase. And that's a very memorable and it's actually quite strong. The more weirdness you had to it, so if you add even just one point of punctuation in a weird spot World Bitcoin Network and you add this, it's going to make it even more difficult. So this is a very strong one.

So what we're going to do to make it a true brain wallet we're going to pretend my computer is not online and that I've actually brought up these web pages, right. So now I'm going to calculate the hash. And a zero two D B blah-blah-blah. And if you did this all on a computer that never went online you would generate the receiving address for that. So pay said here in my wallet details, view details. And I get one G eight W six N. This corresponds directly to my pass phrase, World Bitcoin Network dollar, I can't remember it right now. So remember. I can't even remember the whole thing right now but it's the sort of thing that you want to commit to memory and practice every day. World Bitcoin Network dollar James was here on a sunny day eating lasagna, right.

And you've got a lot of A's. Okay. And you probably want to count them. And then to make it a brain wallet we have to get rid of all past history. So we would close this down and then we close this down and we'd only keep the copy of the public address, right. And then we would take this and we would send our money to the brain wallet. Boom! Okay. That's our one G eight W six N. I will send a dollar to that.

Now people are going to grab these things as soon as they see this video. They're going to see the private keys. They can see the brain wallets. They're going to do all this stuff. Hopefully, you'll be the person to get some of this money and you'll feel sort of the experience of doing it. But what you're going to see is this video will be posted, there will be a date and time and soon after you'll see on the blockchain people taking these little amounts out. Because that's what they love to do. It makes them feel really good. Would be great if people actually kept putting back in and then other people kept taking out so we get lots of practice. But that's not going to happen.

So we send money. And so we've sent money to three different brain wallets that we can remember. World Bitcoin Network is one. We sent one to the moon thing which already people have been dealing with. And we just sent one to this very bizarre one which I can't even remember but it's here on the video so we'll see it. But that's how brain wallet work. And before we go I'm just going to underline the same precautions that they make here. It's very important when creating a brain wallet to use a pass phrase that has a high level of entropy. So it's got to be weird. And what you think is weird might not be very weird for these computers.

Remember, there are people writing programs that are trying out trillions of phrases every day. So anything that's ever been in a book or it's ever been online, any phrase like that is not a good pass phrase. You want to come up with something that when you hit search on Google isn't there. You don't even really want to type it into Google but it's take some phrase, some famous phrase and make it weirder, put some weird symbols in it. Make sure though it's something you can remember because if you're the Italian guy crossing the border with all your value in your head and you forget even one character you may never get the value back.

So that's the bit on brain wallets. Use with caution. Phenomenal sci-fi idea. I think we're going to start to see them appearing in movies all that stuff. So brain wallets. Have fun with them. Play around with small values at first. Maybe move up to more. There's other ways that we might recommend keeping your Bitcoins, paper wallets in safe deposit boxes using multiple signature wallets. There's other ways that you can keep it where you don't have to rely on your brain and if you die, your loved ones may not get your Bitcoins. There's other ways to do things. So remember brain wallets have their time and place, use with caution. Hope that solves everything for you. Hope you enjoy this. Remember to comment, like, subscribe and we'll check you at the next video.

Written by James DeAngelo on February 9, 2014.