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Caesar brute force

Crack a Caesar cipher by showing all 25 possible shifts at once.

Input
Output

Caesar brute force

Paste ciphertext you suspect was encoded with a Caesar shift — also known as ROT-N — and this tool applies all 25 possible shifts at once, so you can scan the list and spot the one that reads as plain text. There is no key to guess and nothing to configure first: since a Caesar cipher only has 25 non-trivial shifts, trying every one of them is faster than reasoning about which shift was used.

This is the standard first move against a Caesar or ROT cipher in puzzle hunts, escape rooms and beginner cryptography exercises: instead of decoding by hand letter by letter, you get every candidate plaintext side by side and your eye does the rest, since real language jumps out immediately among 24 lines of gibberish. It's also handy for CTF challenges and old-school forum obfuscation, where short messages were "encrypted" with a fixed shift and the only practical attack is exhaustive search rather than frequency analysis.

Each of the 25 lines is labelled with its shift number so you can note which one worked, or turn that off if you just want the raw candidates to skim. Numbers pad to two digits by default so the list stays aligned as you scan down it. Only the 26 unaccented Latin letters A–Z are shifted; digits, punctuation, spaces, accented characters and other scripts are copied through untouched in every line, exactly as a Caesar cipher is defined to behave — so mixed-language or formatted text still decodes correctly wherever the cipher applies.

Everything runs locally in your browser. The ciphertext you paste is never uploaded anywhere, which matters if you're working through a private puzzle, a CTF flag, or text you don't want to hand to a third-party service just to try 25 shifts.

FAQ

How is this different from the Caesar cipher tool?
The Caesar cipher tool encodes or decodes with one shift you choose. This tool skips choosing a shift entirely and shows the result of all 25 at once, which is exactly what you want when you don't know the shift used.
Why only 25 shifts and not 26?
A shift of 0 (or 26) leaves the text unchanged, so it can never be a Caesar-encoded message worth decoding — the other 25 cover every possibility.
What if the plaintext uses accented letters or another alphabet?
A classic Caesar cipher only shifts the 26 unaccented Latin letters, so this tool leaves accented characters, punctuation and non-Latin scripts untouched in every line, matching how the cipher is actually applied.
Does this brute-force other ciphers too?
No. It is specific to Caesar/ROT-style single-alphabet shifts. A Vigenère cipher needs a different attack, which is what the Vigenère cipher tool is for.
Is my text uploaded anywhere?
No. All 25 shifts are computed locally in your browser — the ciphertext never leaves your device.