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Preview of Caesar Cipher Decoder

Caesar Cipher Decoder by Pattern Hub

Right-click any selected text to instantly see all 25 Caesar cipher shifts. Fast, offline, no data leaves your browser.

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Extension Metadata

Screenshots
Right-click any selected text to decodeAll 26 Caesar shifts shown at a glanceOne-click copy for any plaintext candidate
About this extension
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.
Developer comments
Open source on GitHub. Issues and PRs welcome:
github.com/KevinGu/caesar-cipher-chrome-extension
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Version
1.0.0
Size
19.69 KB
Last updated
9 days ago (Apr 23, 2026)
Related Categories
  • Web Development
  • Privacy & Security
License
MIT License
Privacy Policy
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Version History
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Tags
  • privacy
  • security
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