Privacy Policy

Last updated: March 26, 2026

1. Introduction

HashNotary ("we", "us", "our") operates the hashnotary.io website and blockchain document certification service. This Privacy Policy explains how we collect, use, and protect your information.

2. Zero-Knowledge Architecture

      Core Principle: Your documents never leave your device. HashNotary uses a Zero-Knowledge Architecture where all file processing (hashing and encryption) occurs entirely in your web browser. We never receive, store, view, or transmit your original documents.
    

3. Information We Collect

3.1 Account Information

Email address (for account creation and communication)
Name (optional, for certificate personalization)
Hashed password (we never store plaintext passwords)

3.2 Document Metadata

SHA-256 hash of your document (a 64-character cryptographic fingerprint)
Timestamp of certification
File name and size (optional, for your reference)

3.3 What We Do NOT Collect

❌ Your original document contents
❌ Document previews or thumbnails
❌ Any data that could reconstruct your document

4. Blockchain Records

Document hashes are recorded on the Polygon blockchain, which is a public, immutable ledger. Once a hash is recorded, it cannot be deleted or modified by anyone, including HashNotary. Blockchain records contain only the cryptographic hash, timestamp, and certifier's wallet address — no personal information or document content.

5. Payment Information

All payments are processed through blockchain transactions on the Polygon network using MATIC or USDC tokens. We do not collect or store credit card numbers, bank account details, or any traditional financial information.

6. Data Security

We implement industry-standard security measures including:

TLS/SSL encryption for all communications
AES-256 encryption for stored vault data
Bcrypt password hashing with salts
Regular security audits and monitoring

7. Data Retention

Account data is retained while your account is active. You may request deletion of your account and associated metadata at any time by contacting us. Note: blockchain records are immutable and cannot be deleted, but they contain only cryptographic hashes — not personal data.

8. Cookies

We use essential cookies for session management and authentication. We do not use tracking cookies or share data with advertising networks.

9. Third-Party Services

Polygon Network: Blockchain transaction recording
Google Gemini AI: Powering our customer support chatbot

10. Your Rights

You have the right to:

Access your personal data
Request correction of inaccurate data
Request deletion of your account
Export your certification records

11. Contact

For privacy-related inquiries: contact@hashnotary.io