Caesar Cipher
Encrypt and decrypt text using the Caesar cipher, locally in your browser.
🔒 Your data is processed locally in your browser and is never uploaded to our servers.
How it works
The Caesar cipher shifts each letter of the alphabet by a fixed number of positions. For example, with a shift of 3, A becomes D, B becomes E and Z becomes C. Decryption applies the same process in the opposite direction.
Examples
With a shift of 3, the text Hello World becomes Khoor Zruog.
Security notes
The Caesar cipher is a historical educational cipher and should not be used to protect sensitive or confidential information. It is not considered secure against modern cryptanalysis.
FAQ
Does it preserve spaces and punctuation?
Yes. Spaces, numbers and punctuation are left unchanged. Only alphabetic characters are shifted.
Can I use a negative shift?
Yes. A negative shift moves letters in the opposite direction.
Is the Caesar cipher secure?
No. The Caesar cipher is mainly useful for learning and demonstrating classical cryptography.