TextEncrypt: Professional Google Docs Text Encryption Add-on

TextEncrypt is a professional password-based encryption add-on for Google Docs that provides text-level data protection using salted, iterated SHA-256 key derivation with HMAC integrity verification. This Google Workspace Marketplace add-on allows document owners to encrypt sensitive text with password protection, preventing readers from accessing confidential information while maintaining collaboration capabilities.

Key Features and Capabilities

Password-based encryption with 10,000 rounds of salted SHA-256 key stretching. Each text segment receives unique encryption keys derived from user password combined with UUID identifiers. HMAC-SHA256 integrity verification ensures data tampering detection. Six-hour session caching eliminates repeated password entry. Batch processing supports encrypting multiple text segments in one selection. Orphan data cleanup tools maintain efficient storage management.

Security Implementation

TextEncrypt encrypts Google Docs text using salted, iterated SHA-256 key derivation and a SHA-256 counter-mode stream cipher with random 16-byte initialization vectors. HMAC-SHA256 verifies integrity before decryption. All encrypted data stored in the document's own add-on properties within Google infrastructure. No external servers involved ensuring complete data sovereignty.

Use Cases and Applications

Ideal for confidential document protection including contracts and legal agreements. Personal information security with encrypted contact details and notes. Business plan protection with encrypted financial projections and strategic information. Research data protection for participant data and confidential findings. Meeting minutes security for confidential discussions and personnel matters. Project documentation protection for API keys and sensitive technical details.

Storage and Licensing

Free 3-day trial includes full encryption and decryption with 1 KB storage per document. Premium license provides 450 KB storage per document. After trial expires decryption remains FREE forever while encryption requires premium license. Premium license unlocks encryption for a one-year duration. Upgrade for $5 USD through Buy Me a Coffee or Gumroad integration. Webhook API verification system for automatic license activation within 2-5 minutes.

Technical Specifications

V3 encryption protocol with format V3:IV:Encrypted|HMAC|Signature. Master key derivation with 10,000 iterations plus 100 iterations per segment. Unique salt per document. Random initialization vectors for each encryption operation. Server-side processing through Google Apps Script requiring internet connection. Only the first user who encrypts in a document can encrypt or decrypt there.

Privacy and Security Considerations

TextEncrypt protects data from readers and read-only users. Editor access limitations: users with editor permissions can view version history containing unencrypted values. Only grant editor access to fully trusted users. The first user who encrypts in a document exclusively controls encryption and decryption there. No password recovery mechanism available - forgotten passwords require history restoration. Session security with user-specific cache expiration after six hours.

Installation and Setup

Available on Google Workspace Marketplace. Installation through Extensions menu in Google Docs. Requires authorization for current-document access. Automatic menu integration after installation. Password is entered twice when encrypting. Minimum recommended password length of 8 characters.

Common Questions and Answers

How does TextEncrypt differ from document-level protection? TextEncrypt provides cryptographic encryption at text level versus access control permissions. Can multiple users encrypt with different passwords? Only the first user who encrypts in a document can encrypt or decrypt there, ensuring consistent password management. What happens when text is deleted? Orphaned encrypted data remains until cleanup tool execution. Is offline usage supported? Requires internet connection for server-side Google Apps Script execution.

Compatibility and Integration

Compatible with all Google Docs documents in Google Workspace and personal Google accounts. Works in desktop browsers including Chrome Firefox Safari Edge (Google Docs mobile apps do not support add-ons). Integration with Google Drive file sharing permissions. Encrypted text is shown as numbered [ENCRYPTED-N] placeholders; decrypted text is restored as plain text.

Performance and Optimization

Optimized batch processing for multiple text segments in a single selection. Efficient storage calculation based on encrypted data size. Real-time storage usage monitoring through Show Storage Usage feature. Automatic warning notifications at 80% capacity threshold. Session-based password caching reduces cryptographic operation overhead during active usage periods.

Support and Documentation

Technical support available through numbrate@gmail.com email. Comprehensive documentation covering installation encryption decryption procedures. FAQ section addressing common use cases and troubleshooting. Premium support included with paid license upgrades. Regular updates and security patches through Google Workspace Marketplace automatic distribution.