© 2026 José Carrillo
Zefer vs Picocrypt
Browser encryption vs desktop encryption. Two free, open-source tools compared.
TL;DR
Zefer works in the browser with no installation and offers advanced access controls (expiration, dual key, IP). Picocrypt is an ultra-lightweight desktop app with CLI, ideal for scripting and offline use. Both are free, open source, and use 256-bit encryption.
Zefer
- AES-256-GCM + PBKDF2-SHA256
- Configurable PBKDF2: 300k / 600k / 1M iterations
- 7 security layers inside the encrypted payload
- Built-in password generator/analyzer and .zefer inspector
- CLI with an MCP server for AI agents
- WCAG 2.1 AA, PWA, dark/light mode
Picocrypt
- XChaCha20-Poly1305 + Argon2id
- Desktop application (Go)
- CLI for automation
- 100% offline, no network
Feature comparison
| Feature | Zefer | Picocrypt |
|---|---|---|
| Strong encryption (256-bit) | ||
| Open source (MIT) | ||
| File expiration | ||
| Dual passphrase | ||
| Reveal key | ||
| Secret question | ||
| IP restriction | ||
| Max attempts | ||
| Compression (Gzip/Deflate) | ||
| Password generator & analysis | ||
| Encrypted-file inspector | ||
| AI integration (MCP server) | ||
| 100% browser-based | ||
| CLI / command line | ||
| Offline use |
Encryption
Zefer uses hardware-accelerated AES-256-GCM, while Picocrypt uses XChaCha20-Poly1305, which is resistant to timing attacks. Picocrypt uses Argon2id for key derivation, considered more resistant to specialized hardware than Zefer's PBKDF2. Both are secure for practical use.
Platform
The main difference is platform. Zefer works in any modern browser with no installation, ideal for quickly sharing encrypted files. Picocrypt requires installation but works fully offline and offers CLI for automating encryption in scripts. If you need to encrypt without internet or integrate with pipelines, Picocrypt wins. If you need to share with anyone who has a browser, Zefer wins.
Access control
Zefer includes 7 access control layers inside the encrypted payload: expiration, dual key, reveal key, secret question, IP restriction, attempt limits, and compression. Picocrypt focuses on solid encryption without additional access layers, which is appropriate for its use case (local encryption).
Choose Zefer if...
- You need files to expire automatically
- You want multiple security layers (dual key, secret question, IP)
- You share sensitive credentials with teams
- You need an installable PWA with full accessibility
Choose Picocrypt if...
- You need to encrypt files offline, without a browser
- You want to automate encryption with CLI in scripts
- You prefer Argon2id over PBKDF2 for key derivation