Certify your documents
The original BTC blockchain notary service.

Instant, anonymous, distributed, and secure proof of existence for any digital document.

1. Registration

Poex stores a unique identifier generated from your document, linked to the time in which it was submitted.

This proof is anonymous, private, and stored in a decentralized system that can't be erased or modified by anyone.

Select a document to get started
Your document will NOT be uploaded.

Drag and drop your document here, or choose a file.
Your file will not be uploaded. Learn more.

Input a Document Hash

Imput the SHA256 checksum hexadecimal digest for your file here.

2. Payment

For the unique identifier to be recorded, we need to create a new transaction in the Bitcoin blockchain.

This certification service is based on the Bitcoin network.

To register the unique proof of your document, a transaction is created with the proof attached to it. For now, the fees for the transaction are to be paid in Bitcoin (BTC).


Documents registered for certification, waiting for payments.

3. Validation

Once a transaction has been created, the unique identifier is stored securely in the blockchain.

Your document's existence is permanently validated by the blockchain even if this site is compromised or down.

The transaction can be consulted from any Bitcoin service.


Documents confirmed in the blockchain.

Technical foundations

This service is based on the original Proof of Existence service designed by Manuel Araoz and Esteban Ordano in 2013.
You can read the history on Wikipedia.

For a detailed description of the technical foundations, please refer to the documentation or directly to the source code.