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Paper backups burn. Metal plates get lost. Cloud services get hacked.

The safest way in 2026 is Shamir’s Secret Sharing on physical Cryptosign Multi-Sig Backup Cards.

What is Shamir’s Secret Sharing (SSS)?

SSS mathematically splits your 12/24-word seed into multiple shares. You decide the threshold (e.g. any 3 out of 5 cards can recover the seed, but 2 cards = nothing).

Why Combine SSS with Cryptosign Cards?

  • Blind Printing = true zero-knowledge
  • 5 material choices: Titanium, Carbon Fiber, PLA, etc.
  • Free air-gapped tool included

Step-by-Step Guide (with screenshots)

  1. Open the free Air gapped Terminal
  2. Paste your seed phrase
  3. Choose threshold (3-of-5 recommended)
  4. Print encrypted shares on your chosen cards
  5. Test reconstruction

Real Customer Setups

3-of-5 Titanium for main wallet
5-of-7 Carbon Fiber for inheritance

Conclusion

Stop trusting paper and single metal plates. Upgrade to proper Shamir SSS with Cryptosign Blind-Printed cards.