ROT13エンコーダー＆デコーダー

このツールの使い方

1. 1

   Type or paste your text into the input box.

2. 2

   Read the transformed result in the output panel directly below as you type.

3. 3

   Click Copy to put the result on your clipboard, then paste it wherever you need it.

4. 4

   To decode ROT13 text, paste it into the same input box; running ROT13 again restores the original.

ROT13とは何ですか？

よくある活用例

• Hide a spoiler, plot twist, or puzzle answer in a forum or chat so readers must deliberately decode it.

• Reproduce or decode classic Usenet and newsgroup posts that used ROT13 to mask punchlines and offensive jokes.

• Teach students the Caesar cipher and modular arithmetic with a concrete, self-inverse example.

• Lightly obfuscate a hint or answer key in documentation or a quiz so it is not readable at a glance.

• Decode ROT13 strings you encounter in CTF challenges, crackmes, or programming exercises.

• Quickly scramble a short note in a non-sensitive context where you only need casual concealment, not real security.

よくある質問