Caesar Cipher & ROT
Encrypts and decrypts with the Caesar shift cipher for any shift 0–25 (including ROT13), and brute-forces an unknown shift by showing all 25 possibilities ranked by how English-like each looks. The 2,000-year-old cipher Julius Caesar actually used.
Runs 100% in your browser — keys and data never leave your device.
Read the full guide to this tool
Notes
- A Caesar cipher has only 25 possible keys, so it falls instantly to brute force — its entire "security" is obscurity.
- ROT13 is Caesar with a shift of 13, its own inverse, and was used on Usenet to hide spoilers rather than to secure anything.
- Runs 100% in your browser — keys and data never leave your device.
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