Skip to main content
answer

What is a Zero-Knowledge Proof?

· Editorial Team · · ~4 min read

Zero-Knowledge Proof — A cryptographic protocol enabling a prover to demonstrate knowledge of a secret to a verifier without disclosing the secret, providing privacy and scalability in blockchain applications.

How It Works

01 The prover generates a proof attesting to a computation or knowledge claim.
02 The verifier checks the proof using a mathematical algorithm — if valid, the statement is true.
03 Common variants include zk-SNARKs (succinct, non-interactive) and zk-STARKs (transparent, quantum-resistant).
04 In blockchains, ZKPs enable private transactions (Zcash) and scalable rollups (zkSync, StarkNet, Polygon zkEVM).

Why It Matters

▸ ZKPs enable privacy-preserving transactions, hiding sender, receiver, and amount.
▸ ZK rollups bundle thousands of transactions off-chain, submitting only a small proof on-chain — scaling throughput 10-100x.
▸ They enable identity verification without exposing personal data (selective disclosure).
▸ ZK technology is a frontier of blockchain R&D, with major investment from Ethereum foundations and L2 teams.

Common Questions

What is the difference between zk-SNARK and zk-STARK?

SNARKs require a trusted setup (initial parameters) but are smaller and faster to verify. STARKs need no trusted setup and are quantum-resistant, but proofs are larger.

Which blockchains use ZKPs?

Zcash (privacy), zkSync Era, StarkNet, Polygon zkEVM, Scroll, and Linea (rollups). Ethereum uses ZK rollups as scaling solutions.

Are zero-knowledge transactions truly private?

Zcash shielded transactions are highly private, but metadata (timing, network) can still leak. Rollup ZKPs focus on scalability, not privacy — transaction data is typically published.

Can quantum computers break ZKPs?

STARKs are believed quantum-resistant. SNARKs based on elliptic curves may be vulnerable to sufficiently powerful quantum computers.

References

  1. https://en.wikipedia.org/wiki/Zero-knowledge_proof
  2. https://ethereum.org/en/zero-knowledge-proofs/
  3. https://vitalik.ca/general/2021/01/26/snarks.html

Related Guides

/blog/ethereum-explained

Ethereum Explained

/blog/what-is-layer-2

What is Layer 2?

Educational content · Not financial advice · Trade at your own risk