Caesar Cipher Decoder
Decode Caesar-shifted text and compare all 25 possible keys.
Plain text
Shift unknown?
Try all 25 Caesar shifts
The most likely English result appears first. Review every possibility below.
How to decode a Caesar shift cipher
Example
Dwwdfn dw gdzq! Attack at dawn! - Paste the Caesar-shifted ciphertext. The decoder applies every possible key from 1 through 25.
- Review the most likely English result first, then compare the complete candidate list when the message is short or ambiguous.
- Choose a known shift in the main converter when you want one exact result. ROT13 is available as a one-click shortcut.
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Frequently asked questions
Which ciphers can this decoder handle?
The current decoder handles Caesar or ROT-style alphabet shifts.
Is my input uploaded?
No. EncodeLab performs this conversion locally in your browser. Your input is not sent to an EncodeLab server or stored by us.
What if I do not know the shift?
Paste the ciphertext and review all 25 possible plaintext results. EncodeLab places the most likely English candidate first.
How does the decoder choose the most likely result?
It compares English letter frequencies and common words. Short or unusual messages may still require you to review several candidates.
Can this break modern encryption?
No. Caesar ciphers are simple historical transformations, not modern encryption.