Security

A seed phrase is a collection of words that can be used to access your cryptocurrency wallet.

You’ll often hear the terms mnemonic seed or mnemonic phrase used to describe the same idea. Some believe that these are poor descriptors, however, as they imply that the phrase needs to be memorized.

Introduced in Bitcoin with BIP39, seed phrases provide users with an easier way of backing up their wallets. If you’ve used a wallet previously, you’ve likely been prompted to write down 12-24 random words like the following:

forget wing follow flip swallow achieve correct view dinner witness hybrid proud

If ever you lose access to your wallet, these can be loaded into any BIP32-compatible wallet to recover your funds. There are 2048 words on the BIP39 wordlist, meaning that a string of 12 words would have 128 bits of security. This means that an attacker would need to perform 2128 operations to guess a 12-word seed. It may look like a small number, but it certainly isn’t. It’s practically infeasible for even the most well-resourced attackers to crack this sequence (for now). The longer the seed, the more secure it is.

Seed phrases – as opposed to private keys – leave less room for human error when it comes to backups, as they're easier to record and transmit. Better still, they’re capable of generating not just one, but a colossal amount of keys from a master one. This allows users to avoid address reuse as, with a single seed, they can create a seemingly infinite number of receiving addresses.

Seed phrases are not cryptocurrency-specific. They can be used across hundreds, so that one seed can actually be used to recover an entire portfolio of coins and tokens. The majority of leading wallets allow the user to recover their funds with a seed phrase, provided they have correctly recorded it.

Do’s:

  • If you are worried about losing your seed card to natural disasters that can cause water or fire damage, the safest way to store your recovery seed is on a backup tool like Cryptosteel. It’s an indestructible tool that leaves your security in your own hands — no third party involved. It’s even manufactured with a way to attach a padlock, for extra security no matter where you keep it.
  • You want to keep your recovery seed safely out of sight. You can keep it locked in a safe in your own house, or you can find a secure alternative away from your property. Although keeping your recovery seed offsite can be inconvenient when it’s time to update to the latest firmware, security and convenience are often inversely related.
  • To protect your recovery seed card while it’s in your safe, laminate it. Laminators are fairly inexpensive, and it will keep your card safe from accidental water damage or other stains and physical damage like tearing or smudging. We don’t recommend taking your card in to a shop to get it laminated. You are the only person who should ever see your recovery seed.
  • You can also store more than one copy of your recovery seed. You receive two cards in each Trezor box. They should be stored separately to increase your own security and to lessen the chance of losing your recovery seed through accident or theft. One copy can go in your safe at home, and the other can be stored offsite, in a bank for example.
  • You can keep your recovery seed safe from physical damage by engraving it on a steel plate. Again, engraving tools are fairly inexpensive, and are especially worth the investment if you have more than one recovery seed to protect.
  • As a final tip, include access to your recovery seed in your will. You want to feel as secure as possible, but don’t forget to plan for any eventuality. You can read online about multiple cases of people who died and did not leave their passphrase or recovery seed accessible to their family.
  • As a final tip to protect your device and add one more layer to your recovery seed, you can use the passphrase function for your wallet.

Donts Precautions for Backup Keys /Seed Phrase

  • The number one don’t that we can warn you against is this: Never store your recovery seed in any digital form.
  • Don’t take a picture of it.
  • Don’t put it in an email.
  • Don’t store it in any password manager.
  • Don’t save it in a Google doc.
  • Don’t send it in a text message.
  • Don’t print it out.
  • Don’t send it in a fax.
  • Some people use a USB to store their recovery seed, but even that can be compromised in certain situations. Why risk it?
  • You should never carry your recovery seed with you. You could lose it or it could even be stolen from you.
  • Knowing how important your recovery seed is to protecting your assets and restoring your wallet after updates can be a little stressful. Hopefully these do’s and don’ts can help you decide the best way to store your recovery seed so you can continue using your Trezor hardware wallet stress-free.