offline bitcoin storage guide

requirements: computer, coldcard, battery, usb cable, microsd card, card reader, dice

This guide will get you setup with using bitcoin in a reasonably easy, affordable, and secure way. It is best to keep bitcoin keys offline and never connected to the internet. Someone would need physical access to steal money, similar to gold secured in a safe. After you get comfortable with this setup you can easily upgrade your security and privacy without changing the software you are using.

this setup is relatively cheap for the security it provides
~$150: coldcard + computer
~$450: recommended full setup: bundle + card reader + dice + computer

  1. buy coldcard
    a. best not to ship to your house for privacy reasons but they claim to delete customer records after 120 days
  2. check bag for tamperenter image description hereenter image description here
  3. open bag, check device for tamper
  4. download newest firmware to computer
  5. load it on to microsd card
  6. remove microsd from computer, insert into coldcard
  7. connect coldcard to battery, power on
    a. some battery packs do not stay on for low power devices, the coldpower offered directly from coinkite is great
  8. check bag number on device
  9. use microsd to install latest firmware: Advanced > Upgrade >From MicroSD
  10. create pin
  11. create new wallet
  12. press 4 to add dice
  13. roll at least 100 times
    a. this adds your own entropy to the built in coldcard entropy, so you are not solely trusting the coldcard’s random number generator
  14. backup your wallet by storing the secret backup words somewhere safe in steel
    a. this is called your seed
    b. anyone with access to these words can spend your bitcoin
    c. never enter them into your computer
    d. enter them directly into a coldcard when restoring from backup
    e. for additional security use SeedXOR feature in coldcard settings to split your seed into two parts, both sets of words would be required to recover/spend your bitcoin, store them separately on steel
    f. if you have a second coldcard, practice the recovery process by recovering the seed words into the second coldcard, if you did the back up correctly both coldcards should show the same receive addresses
  15. download and install sparrow wallet
  16. follow the steps to add coldcard
  17. OPTIONAL: For better privacy install and run Bitcoin Core on the same computer to easily use Sparrow with your own node


If you find this guide helpful support my work with bitcoin. donate

The content above provides education as to general privacy and security practices when using bitcoin. Should you choose to apply the practices described in linked content with bitcoin you own now or may purchase in the future, you do so at your own risk and I shall in no event be liable for any financial loss suffered. Nothing shall be construed as providing consulting, financial advice or general advice as to securing bitcoin.