ROT13 Encoder / Decoder
Apply the ROT13 substitution cipher to your text — rotating each letter 13 positions in the alphabet. One click encodes; one more click decodes it back.
What Does This Tool Do?
ROT13 is a simple letter substitution where each letter is replaced by the letter 13 positions after it in the alphabet. Since the alphabet has 26 letters, applying ROT13 twice brings you back to the original text — so the same tool encodes and decodes. It's traditionally used to hide spoilers, puzzle answers, or mildly sensitive text from casual readers.
Key Features
How to Use This Tool
- Paste your text into the Input box.
- Click Convert to apply ROT13.
- To decode: paste the ROT13 text and click Convert again — same operation.
How It Works
Each letter in your text is shifted 13 positions forward through the alphabet (A becomes N, B becomes O, and so on). When it reaches the end, it wraps around (N becomes A, Z becomes M). Non-letter characters are passed through unchanged.
Common Use Cases
Frequently Asked Questions
How do I decode ROT13?
Apply ROT13 again — the encoding and decoding operations are identical.
Is ROT13 secure?
No — ROT13 provides no real security. Anyone who knows about it can decode it instantly. Use proper encryption for anything sensitive.
Related Tools
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