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Tips for Caesar cipher
This is a teaching cipher — not suitable for real secrecy.
Try all 25 shifts when the key is unknown (brute force is trivial).
Preserve case and spacing only if your exercise requires it.
Use it to illustrate frequency analysis, not to protect data.
Never ship Caesar-encrypted production secrets.
A teaching cipher, not real encryption
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Caesar shifts letters by a fixed amount. It is useful to see substitution by hand — it is trivial to break and must not protect real data.
Use it in class, puzzles, or CTF warm-ups. For secrets, use modern cryptography (the AES/RSA demos are still demos).
Shift a message
Enter a sample sentence
Use fake text. Do not paste production secrets into a toy cipher.
Choose the shift
A shift of 13 is ROT13; other offsets are the same idea.
Read the ciphertext
Decrypt with the inverse shift to confirm you understand the mapping.
Caesar cipher FAQ
Is Caesar secure?
No. There are 25 interesting shifts for English letters. Computers try them instantly.
Does this encrypt files?
It only shifts text in the page. It is not a file vault.
Why teach it then?
It shows substitution and keys without the machinery of AES. Then you graduate to real primitives.