ROT13 / Caesar Cipher
17 toolsEncode or decode text with a Caesar cipher.
Runs in your browser — your files and text stay on your device
A complete text toolkit — convert case, count words, diff text, sort and dedupe lines, find & replace with regex, generate fancy Unicode text and Lorem Ipsum, check readability, use text-to-speech and speech-to-text, normalize whitespace, apply a Caesar cipher, and check palindromes. All processing happens in your browser tab.
CaseCountDiffLorem IpsumSlug GeneratorRemove DuplicatesWord FrequencyText ReverseLine SorterFind & ReplaceFancy Text GeneratorReadability ScoreText-to-SpeechSpeech-to-TextWhitespace NormalizerROT13 / Caesar CipherPalindrome Checker
Shift13
Output
How to use this tool
- 1Type text and pick a shift amount (13 = classic ROT13).
- 2The ciphered text updates instantly.
- 3Running the same shift again on the output decodes it back (for ROT13 specifically).
Frequently asked questions
Is this secure encryption?
No — a Caesar cipher is trivially breakable and meant for fun/obfuscation, not real security.
Why does ROT13 decode itself?
Shifting by 13 twice returns to the original letter, since 13 + 13 = 26, a full alphabet rotation.