Playfair Cipher (Encode & Decode)
Security ToolsEncrypt letter pairs with a 5×5 keyword square
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History
All history →Playfair Cipher (Encode & Decode) — at a glance
Lock or unlock a message with the classic Playfair square.
How to use it — step by step
Your text and a keyword. Letters are paired up and swapped using a 5×5 grid built from the keyword.
Add your text
Paste or type your input into the box. The Sample button fills in an example.
Choose the options
Pick the mode and settings you need. Results update when you run the tool again.
Press Run Playfair
The result is made instantly inside your browser.
Copy the result
Use the Copy button, or send it to another tool.
Pro tips
Small things that make the result better.
Quick facts
Frequently Asked Questions
How does Playfair work?+
The keyword fills a 5×5 grid. Each pair of letters is replaced by the letters in the same row, same column or the opposite corners of a rectangle.
Is Playfair secure?+
No. It was used in the field long ago but is easy to break today. Use it for puzzles and learning.
Is my data safe?+
Yes. Everything runs inside your own browser. Your text, files and images are never uploaded to any server.
Is this tool really free?+
Yes — completely free, no signup, no watermark and no usage limit.