What is Poseidon Hash?

Poseidon is a modern hash function designed specifically for use in zero-knowledge proof systems like zk-Rollups and zk-STARKs.

Unlike older general-purpose hashes (like SHA-2 or SHA-3), Poseidon is built to be extremely efficient inside zk-proofs— which means faster, cheaper, and smaller proofs.

Key Features

  • ZK-Friendly Design — Poseidon is optimized for use inside arithmetic circuits — ideal for zk-STARKs.
  • Fast in Proofs, Slow to Break — It reduces the time and size of zero-knowledge proofs, but still maintains strong cryptographic security.
  • Post-Quantum Ready — Based on hash functions, not elliptic curves—safe from quantum attacks.
  • Flexible & Efficient — Poseidon can be customized for different field sizes and applications, giving developers more control.

Why It Matters

Traditional hash functions like SHA-256 are slow and processor intensive inside zk-proofs. Poseidon cuts down:

  • Proof size
  • Proof generation time
  • Computation cost

In Xcoin, Poseidon is used as part of its zero-knowledge infrastructure—
ensuring that every private transaction is lightweight, fast, and quantum-secure.

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