SM4 Encryption Tool
Encrypt and decrypt text using China's SM4 block cipher algorithm. All processing is done in your browser - no data is sent to any server.
Key Management
Instructions
- Generate a random key or enter your own 16-byte key
- Enter the text you want to encrypt or decrypt
- Click the appropriate button to perform the operation
- Use the Copy buttons to copy the key or result to your clipboard
Note: Keep your encryption key secure. Anyone with the key can decrypt your messages.