About ProofChain

Proof-of-existence for real-world documents.

ProofChain lets you anchor the existence of any digital artifact on Ethereum Sepolia, without revealing its contents. It's a lightweight, verifiable timestamp for your most important files.

What is ProofChain?

ProofChain is a proof-of-existence dApp. Instead of uploading full documents to a blockchain, you upload them to IPFS and store only a small fingerprint (hash / CID) on Ethereum. This creates an immutable record that the file existed at a specific point in time, owned by a specific wallet address.

What problem does it solve?

Many workflows rely on private documents—contracts, NDAs, designs, research, invoices. Proving that a file existed before a certain date is hard without trusting a central system. ProofChain gives you an independent, tamper-resistant timestamp and ownership record for those files.

Why use blockchain?

Blockchains like Ethereum provide immutable history and global verifiability. Once a proof is written on-chain, no single party can alter or delete it. Anyone can verify the proof using standard Ethereum tooling, even without interacting with this app.

Real-world use cases

  • Proving authorship of creative work (designs, manuscripts, music, code).
  • Anchoring contract versions or NDAs without exposing sensitive terms.
  • Timestamping research data, experiment results, or IP disclosures.
  • Providing verifiable receipts, invoices, or compliance documents.

How ProofChain works

  1. Upload a file and pin it to IPFS to get a content identifier (CID).
  2. Store the CID, a title, and your wallet address on Ethereum Sepolia.
  3. Share a public verification link so others can independently validate the record.

Only the hash / CID and minimal metadata are stored on-chain. The document contents stay off-chain and under your control.