Block Vault makes it safe and easy to store the mnemonic phrases you have as backups of your crypto currency wallets. Block Vault solves your backup issue if you are using a hardware device like a Trezor, Ledger, or Nano, or a software wallet like Jaxx, Bread, Exodus to store your Bitcoin, Litecoin, Ethereum, Ripple, and other currencies.

The problem with that list of 12, 15, 18, 21 or 24 words is that you need to keep it safe. If it gets stolen, you could be out a lot of money. If it gets lost or destroyed, same problem. Some people have suggested splitting the list into two parts, and storing them in separate locations. The only problem with that solution is you just doubled your chances of loss or destruction.

Block Vault helps solve that problem by using a magical data property known as parity. We generate three lists from your single list. Any single list is worthless on its own, but with any 2 of 3, you can recover your backup phrase.

With these 3 word lists, you can store each at a separate location, increasing both your security, and the ability to recover your mnemonic seed if the need ever arises. We'd suggest locations like your home safe, your office, a safe deposit box, a trusted friend or family member. The best part is, if you choose to use the "Plausible Deniability Method," which is on by default, each of your 3 backup keys will appear to be a valid mnemonic, so anyone who gets their hands on any of your three lists will likely think you just have an empty wallet.

Let's get started!

Here is how it works. If your list has an even number of words, we suggest using the "Easy Method" to generate your backup (this is the default method). If your mnemonic key has an odd number of words (15 or 21 - or you simply want to mix things up a little more), choose the "Bit Mix Method."

You enter your backup phrase as shown here.

By default, the "Plausible Deniability" option is on, and the length should be set to the length of your mnemonic phrase. With this option, each backup key generated will be a valid mnemonic according to the "BIP 39" specification. This means that anyone who finds (or forces you to hand over) any one of your backup keys will believe that they have a valid key. You can adjust the length of the generated backup keys, or you can completely turn off this option.

Now tap "Generate Backup Keys."

Your 3 backup phrases will now be generated. You'll notice some similarities between your backup phrase and Backup Key 1 and Backup Key 2 when using the Easy Method  -  more on that later. We'd recommend using three separate pieces of high quality paper to store your three backup phrases, or a more permanent solution (for example, metal etching).

If you unselect the "Plausible Deniability" option, each backup phrase will be shorter.

You can also print each backup phrase independently with any connected Air Print printer by tapping the "Print" button above each backup phrase.

If you need to restore your mnemonic phrase, you can enter any two of your Backup Keys on the Restore Screen -  the order does not matter.

Tap on Restore Mnemonic, and your original phrase will appear.

If you ever need to reconstruct your backup phrase and you use the Simple Method, you don't even need to use our Restore feature (though you are certainly free to do so) if you have Backup Key 1 and Backup Key 2. All you need to do to reconstruct your backup phrase is to recall the number of words in your original mnemonic, divide that number by 2, and take that number of words from the beginning of Backup Key 1, and add to that the same number of words from the beginning of Backup Key 2.

Here's the explanation of how our method works: We take your word list and translate it to the corresponding 11 bit numbers according to the BIP 39 specification. Depending on the method selected (Easy or Bit Mix), we split that list of numbers in half at the bit level. We add to that 3 bits of information on the encoding, and append a checksum. We then use the exclusive-or operator to generate a third list of numbers. With the plausible deniability method, we generate a valid mnemonic by first calculating a checksum of the three calculated lists from above, add that information, and then calculate the checksum according to the BIP 39 specification. When you want to restore your key, we essentially reverse the entire process.

We know that security is paramount. Block Vault uses no third party APIs other than those natively provided. None of the information you enter is ever transmitted, it all stays local. The only time Block Vault will ever access the Internet is to load this help file. If you send Block Vault to the background, you will find that any information you may have entered or generated in the app is cleared after 10 minutes of inactivity. Of course, we would highly recommend using the "Clear Data" buttons to clear the data after you have generated it and had a chance to write it down or print it.