Timestamp Document on Blockchain

WHAT IT DOES

Timestamp Document on Blockchain enables you to create an immutable proof of existence for any document by storing its cryptographic hash on the blockchain. This process, known as blockchain timestamping, provides verifiable evidence that a document existed at a specific point in time without revealing its contents. The tool takes a document file, computes its Keccak-256 hash, and simulates storing that hash on the blockchain via a transaction. The resulting transaction hash serves as a permanent, tamper-proof timestamp that can be independently verified by anyone. This is essential for intellectual property protection, legal evidence, audit trails, and any application requiring proof of document integrity and timestamp. The tool provides clear output showing the document name, size, hash, and transaction hash.

HOW TO USE

Connect your wallet using the BGWallet connector (required for context). Click the file input to select a document from your local system. Optionally, enter a document name and description. Click "Timestamp Document" to process the document. The tool computes the document hash and simulates a transaction to store it on the blockchain. The tool displays the document name, size, the Keccak-256 hash, and the transaction hash. You can copy the hash to your clipboard for verification, or view the transaction on the blockchain explorer. The result includes a detailed breakdown showing the document details and timestamping results.

TECHNICAL MECHANISM

This tool implements document timestamping by computing a cryptographic hash of the document and storing it on the blockchain. The timestamping process: (1) the document is read as an ArrayBuffer; (2) the Keccak-256 hash of the document bytes is computed using ethers.js; (3) a transaction is simulated to store the hash on the blockchain (in a real implementation, this would be sent to a timestamping smart contract); (4) the transaction hash and block timestamp serve as the immutable proof. The Keccak-256 hash is a one-way function that uniquely identifies the document content—any change to the document will produce a different hash. The blockchain provides a permanent, tamper-proof record of when the hash was stored. All computation is performed locally in the browser with no data sent to external servers except for the transaction itself.

WHAT IT CANNOT SEE

This tool cannot guarantee that the timestamp will be accepted as legal proof in all jurisdictions—legal recognition varies by jurisdiction. It does not verify the document's content or authenticity beyond the hash; it only proves the document existed at the time of timestamping. The tool cannot recover the original document from the hash; the hash is one-way. It does not support timestamping without sufficient gas fees; transactions require gas. The tool cannot guarantee the transaction will be mined within a specific timeframe; mining times vary. It does not support batch timestamping of multiple documents in a single transaction; each document must be timestamped separately. The tool cannot verify the document's integrity without the original file; the hash must be recomputed from the original document. It does not support private or permissioned blockchains; the tool works with public EVM chains.

PLEASE NOTE

This tool is designed for developers and users needing immutable proof of document existence. The Keccak-256 hash uniquely identifies the document content. The blockchain timestamp provides a permanent, verifiable record. For production use, ensure you have sufficient gas fees for the transaction. Always verify the timestamp by recomputing the hash from the original document. The tool is intended for testing, development, and educational purposes. The timestamp is stored on the blockchain and cannot be altered or removed.