Caesar Cipher Encoder, Decoder & Bruteforce
Shift cipher with instant all-25 bruteforce.
About this tool
The Caesar cipher shifts each letter a fixed distance through the alphabet — Julius Caesar reportedly used a shift of 3. With only 25 possible keys it falls to exhaustion instantly, which is exactly what the bruteforce tab does, ranking every candidate by English letter frequency.
Like everything on encrypt.tools, this runs entirely in your browser — nothing you enter is transmitted or stored.
Frequently asked questions about Caesar Cipher
How do I break a Caesar cipher without the key?+
Use the bruteforce tab — with only 25 possible shifts, it tries all of them and ranks results by how English-like they look, so the plaintext is usually obvious at a glance.
What shift did Julius Caesar use?+
Historically a shift of 3, moving A to D. This tool supports any shift from 1 to 25.
Is the Caesar cipher secure?+
Not at all — it's the textbook example of a trivially breakable cipher, valuable only for learning and puzzles.
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