The text encryption tool encrypts and decrypts plain text using one of four symmetric algorithms — AES, TripleDES, Rabbit, or RC4. Enter plaintext and a key to get a Base64-encoded ciphertext; paste that ciphertext back with the same key and algorithm to recover the original. All computation runs in the browser; nothing is transmitted.
Which Algorithm to Choose
AES — recommended
- US federal government standard, most widely audited symmetric algorithm
- Highest security with fast speed
- Default choice for almost every use case
TripleDES — legacy compatibility
- Applies DES three times — less secure than AES and slower
- Only use it when integrating with an older system that requires 3DES
Rabbit — throughput priority
- Stream cipher, very fast with low resource usage
- Fewer public audits than AES, but acceptable security for non-critical text
RC4 — avoid
- Multiple known vulnerabilities — do not use for new work
- Only relevant for compatibility with very old systems
Key Strength Matters as Much as Algorithm Choice
All four algorithms use key derivation to turn your passphrase into an internal key. A weak passphrase like 123456 or password makes even AES trivially crackable via dictionary attack.
- Use 16+ characters mixing letters, numbers, and symbols
- Never store the key in the same location as the ciphertext
- Transmit the key through a separate, secure channel
Output Format
Encrypted output is a Base64-encoded string, for example:
U2FsdGVkX18vLZAjnNztRaRDUdr8Mz1DIeAsrY7Q1UA=
Base64 contains only printable ASCII characters, so it is safe to store in JSON, pass in a URL parameter, or write to a config file. To decrypt, paste this string back, select the same algorithm, and enter the same key.