Atbash Cipher

Self-inverse classical cipher mapping A↔Z, B↔Y, ...

Tool Text Codecs Updated Apr 20, 2026
How to Use
  1. Type or paste your input on the left.
  2. The result appears live on the right - no buttons needed.
  3. Copy the output with one click.

About this codec

Self-inverse classical cipher mapping A↔Z, B↔Y, ...

About Atbash

Atbash is a self-inverse substitution cipher mapping A↔Z, B↔Y, and so on. This tool lets you transform text with Atbash instantly and entirely in your browser. It is commonly used for puzzle hunts and learning classical ciphers.

💡Worked example: HELLOSVOOL
⚠️Atbash is a classical cipher, not real security — it is trivially broken and is meant for puzzles, learning, and fun. For confidentiality use modern encryption, not a classic cipher.

How to use it

Type or paste your text into the box and it turns into Atbash live as you type — everything runs locally in your browser. Learn more in the Knowledge Base.

Frequently Asked Questions

Does this leave my browser?

No - the conversion runs entirely in JavaScript on this page.

What does Atbash look like?

HELLO becomes SVOOL. Atbash is typically used for puzzle hunts and learning classical ciphers.

Does my text leave my browser?

No. The Atbash conversion runs entirely in JavaScript on this page — nothing is uploaded, and it works offline.

Is Atbash secure?

No — Atbash is a classical cipher that is easy to break. Use it for puzzles and learning, and use real encryption when you actually need confidentiality.

Common Use Cases

Puzzle hunts and learning classical ciphers

Atbash is commonly used for puzzle hunts and learning classical ciphers — produce it here in one step.

Learning & puzzles

See how text maps to Atbash — handy for coursework, CTF challenges, and puzzle hunts.

Private by design

Everything runs locally in your browser, so you can paste sensitive text without it leaving your device.

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