Caesar Cipher Decoder 作成者: Pattern Hub

Decode Caesar ciphers in one right-click — no copy-paste, no website detour.

Select any encoded text on any web page, right-click, and choose "Decode as Caesar Cipher". A new tab instantly shows all 26 possible shifts (0–25), so you can eyeball the plaintext in seconds. Perfect for CTF challenges, puzzle games, cryptography homework, or any time you run into rotated text online.

Features
* One right-click → all 26 shift candidates at once
* Click-to-copy on any row
* Handles selections up to 2,000 characters
* Unicode-safe: only A–Z / a–z are shifted; digits, punctuation, CJK, and emoji pass through unchanged
* Clean result page — no ads, no popups, no upsells

Privacy & Security
* 100% offline — makes zero network calls
* No tracking, no analytics, no telemetry
* No data storage — nothing is saved, anywhere
* Only one permission: contextMenus (for the right-click menu item)
* Open source: github.com/KevinGu/caesar-cipher-chrome-extension

Your selected text never leaves your browser.

Want More Ciphers?
This extension is deliberately single-purpose. For Vigenère, Atbash, Autokey, Rail Fence, Playfair, ROT47, frequency analysis, and 20+ other classical ciphers with step-by-step walkthroughs, visit the companion web toolkit at caesarcipher.org.

License: MIT. Source code and issue tracker on GitHub.