ROT13 / Caesar Cipher: guide & how to use

Apply a Caesar cipher with any shift from 1 to 25. ROT13 (shift 13) is the classic default. Encode and decode by adjusting the shift. Non-letter characters pass through unchanged. This guide is part of our guides library in the Text & writing category—Word counts, case styles, lorem ipsum, citations, similarity highlights, and diffs for drafts and homework.

What this tool does

ROT13 / Caesar Cipher — Shift letters by a configurable offset (default 13). It fits alongside other utilities on AI Tool Hub so you can solve small problems quickly without installing desktop software.

When it helps

Reach for this tool when your work overlaps with topics like: rot13, caesar, cipher, shift, encrypt, decode. Teams use these utilities for ad hoc checks during development, studying, content drafting, and light business calculations—always double-check critical numbers against your own policies or professionals when stakes are high.

How to use it

1. Type or paste text in the input box.
2. Set the shift value (default 13 for ROT13).
3. Copy the shifted output. To decode, apply 26 minus the original shift.

Common questions

Is this encryption?

No. Caesar ciphers are trivially breakable and are for fun or obfuscation, not security.

Related tools

Pair this workflow with other utilities on the site:

• Morse Code Translator

  Translate text to Morse code and back.
• NATO Phonetic Alphabet

  Spell out text using the NATO phonetic alphabet.
• Hash Generator

  MD5, SHA-1, SHA-256, SHA-512 from text in your browser.

Privacy

Like most utilities in this category, ROT13 / Caesar Cipher runs locally in your browser after the page loads—your content is not sent to our servers for processing.