Text Encryption Tool - AES-256 Encrypt & Decrypt
Encrypt and decrypt text securely with AES-256-GCM. Password-based, browser-only, zero data transmission.
What Is AES-256 Text Encryption?
AES-256-GCM (Advanced Encryption Standard with Galois/Counter Mode) is a military-grade encryption algorithm that protects data with a 256-bit key. This tool uses your password to derive an encryption key via PBKDF2 (600,000 iterations), then encrypts your text entirely in the browser. The result is a Base64-encoded string that can only be decrypted with the same password.
How to Encrypt and Decrypt Text
- Choose Mode — Select the Encrypt or Decrypt tab
- Enter Text — Type or paste text to encrypt, or paste Base64 ciphertext to decrypt
- Set Password — Enter a strong password (used for both encryption and decryption)
- Process — Click the button to encrypt or decrypt
- Copy Result — Copy the output to share or store securely
Why Use This Encryption Tool?
- Military-Grade Security — AES-256-GCM is the same standard used by governments and financial institutions
- Zero Data Transmission — All encryption and decryption happens in your browser using the Web Crypto API
- Strong Key Derivation — PBKDF2 with 600,000 iterations and random salt protects against brute-force attacks
- Authenticated Encryption — GCM mode ensures data integrity, detecting any tampering
- No Account Required — Use instantly without sign-up or installation
FreeToolbox vs Other Encryption Tools
| Feature | FreeToolbox | DevGlan | AnyCript |
|---|---|---|---|
| Privacy | Browser-only | Server-based | Server-based |
| Algorithm | AES-256-GCM | AES-256-CBC | AES-256-CBC |
| Key Derivation | PBKDF2 (600K) | None shown | None shown |
| Authenticated | Yes (GCM) | No (CBC) | No (CBC) |
| No Account | Yes | Yes | Yes |
| Open Source Logic | Yes (inspect source) | No | No |
FAQ
Is my text sent to any server?
No. All encryption and decryption is performed entirely in your browser using the Web Crypto API. No data leaves your device.
What happens if I lose the password?
The encrypted text cannot be recovered without the exact password. There is no password reset or recovery mechanism. Store your password securely.
What encryption algorithm is used?
AES-256-GCM (Advanced Encryption Standard, 256-bit key, Galois/Counter Mode). The key is derived from your password using PBKDF2 with 600,000 iterations and a random 16-byte salt.
Can I decrypt text encrypted with other tools?
No. This tool uses a specific format (salt + IV + ciphertext encoded in Base64). It can only decrypt text that was encrypted with this same tool.
How strong should my password be?
Use at least 12 characters with a mix of uppercase, lowercase, numbers, and symbols. The password strength indicator shows how strong your password is. Even with PBKDF2 protection, a weak password can be guessed.