ROT13 rotates Latin letters by 13 positions—a self-inverse cipher where applying it twice returns the original text. It is folklore for hiding puzzle answers an
Overview
Encode and decode ROT13 text online. Spoilers, puzzles, and jokes—free ROT13 tool, copy paste, instant results. Free in your browser on Case Modify—no account…
What this page covers
ROT13 rotates Latin letters by 13 positions—a self-inverse cipher where applying it twice returns the original text.
Quick answer
Encode and decode ROT13 text online. Spoilers, puzzles, and jokes—free ROT13 tool, copy paste, instant results. Free in your browser on Case Modify—no account… Use it in a browser with no account required, then review the output before publishing or shipping.
About ROT13 Encoder/Decoder
ROT13 rotates Latin letters by 13 positions—a self-inverse cipher where applying it twice returns the original text. It is folklore for hiding puzzle answers and forum spoilers.
How to Use ROT13 Encoder/Decoder
Paste plain or ROT13 text. Copy output—encode and decode use the same operation. Share puzzle hints without glaring spoilers in the feed.
When to Use ROT13 Encoder/Decoder
Puzzles: Hide answers in plain sight. Teaching: Introduce substitution ciphers before modern crypto. Memes: Nudge readers to decode a line.
Why Use This ROT13 Encoder/Decoder?
One click beats paper cipher wheels for quick online posts.
Unicode vs HTML formatting
Real security needs modern cryptography. ROT13 is a toy transform, not protection for secrets.
Platform compatibility
Forum spoilers, geocaching hints, and classroom demos. Anyone who knows ROT13 can decode instantly.
How to use this tool
- Paste plain or ROT13 text.
- Copy output—encode and decode use the same operation.
- Share puzzle hints without glaring spoilers in the feed.
Getting started
ROT13 rotates Latin letters by 13 positions—a self-inverse cipher where applying it twice returns the original text. It is folklore for hiding puzzle answers an
Privacy and local processing
Rot13 Encoder Decoder runs in your browser on Case Modify. Typical conversions do not upload your pasted text to our servers for processing.
You still share data with your browser vendor and network as with any website; see our privacy policy for analytics and ads. When you work with secrets, credentials, or personal data, review the output locally before you publish or send it.
Details: privacy policy.
Before you publish
Unicode styling, formatted code, and converted units can look correct in the preview but fail in the target app because of font support, line breaks, or platform limits.
Test a short sample in the destination (bio field, IDE, CMS, or spreadsheet) before you paste a long block.
Workflow tips: how Case Modify works, documentation hub.
Limits to keep in mind
Free browser utilities excel at quick edits, classroom exercises, and copy-paste formatting. They are not a replacement for licensed design software, production build pipelines, or compliance review.
When a platform rejects styled Unicode, fall back to plain ASCII from a case converter or remove formatting before you submit final copy.
Frequently asked questions
Is ROT13 secure?
No. It is obfuscation for fun, not confidentiality.
Does ROT13 change numbers?
Typically only A–Z/a–z rotate; digits and punctuation stay put.
Examples
| Before | After | Notes |
|---|---|---|
| Hello | Uryyb | |
| Uryyb | Hello | apply again |
| APPPBARK — spoiler style |
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