As your business grows and you begin purchasing bitcoin to save your money, you will want to store your private key in a manner that is not connected to the internet 24/7 like your BTCPay server or mobile wallet. If you shut down your server and delete your mobile wallet, the private keys would then be considered cold because they are no longer stored on an internet connected device.
With cold storage, there are a number of additional methods to keep them safe from water, fire, theft and peeping eyes.
- Words written on paper, if possible, having a duplicate stored in a second location helps minimize the cons. Recommended for hot storage.
- Pros: Easy to create, store/hide. Can be sealed in a bag to protect from water.
- Cons: Easily destroyed by flood/fire. Ink and pencil fade over time.
- Memorize your private key, not recommended as the only method of storage in any situation except under duress.
- Pros: Portable for travel.
- Cons: Memory failure or death causes complete loss of access.
- Stamped steel, comes in many types, this video is a great reference.
- Pros: Best protection for fire and water damage.
- Cons: Some types require some handy work to create and can be found with a metal detector.
- Non air gapped electronic hardware device, a device that will generate your private key, store it and allow you to sign a bitcoin transaction. Non air gapped means you must connect it to the computer to sign a transaction, this is done using a usb port. You must also write your words on paper in the event the device fails or is lost. We do not recommend any products in this category; if found they can be hacked and provide access to your private key.
- Pros: Makes signing a transaction quick.
- Cons: You will need to remember a pin/password to get access to the device.
- Air gapped electronic hardware wallet device, an air gapped device uses a mini camera and mini LED screen to pass qr codes from and back to your computer to sign a transaction. You can learn more about SeedSigner, which is a recommended choice. Purchase one already built or build it yourself.
- Pros: Never connected to internet, best option for complete privacy and large amounts of money.
- Cons: Manual entry of words takes approximately 30 minutes to complete a transaction.
