Secret Sharing – Free Online Utility

Split secrets into multiple parts using Shamir's scheme.

Understanding Shamir's Secret Sharing

Shamir's Secret Sharing (SSS) is an cryptographic algorithm that allows a "secret" to be divided into multiple "shares". To recover the original secret, a certain minimum number of shares (the threshold) must be combined. Even with one share less than the threshold, the secret remains completely unrecoverable.

Practical Applications

  • Distributed Backup: Split your recovery phrase into 5 shares and give them to 5 trusted people. If you require a threshold of 3, you can recover your funds even if 2 people lose their shares or become unavailable.
  • Corporate Control: Require 2 out of 3 executives to combine their "keys" to authorize a high-value transaction.
  • Inheritance Planning: Distribute shares of a master password to family members and a lawyer.

Privacy Note

This implementation runs entirely in your browser. No shares or secrets are ever sent to a server. However, for maximum security, we recommend using this tool only on a trusted, secure device.

Frequently Asked Questions

Shamir's Secret Sharing (SSS) is an algorithm created by Adi Shamir. It allows you to split a secret into N parts (shares), such that any T of them (the threshold) can reconstruct the secret, but T-1 parts reveal absolutely nothing about the secret.
If you have fewer shares than the threshold (T), it is mathematically impossible to recover the secret. This makes SSS perfect for distributed backup of sensitive information like recovery phrases.
This tool uses a simplified version of SSS for demonstration and basic utility. For ultra-high security needs (like multi-million dollar crypto wallets), dedicated hardware-based SSS implementations are recommended.

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