encode
decode
a
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b
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Text to encode
Hello World
Encoded
Decode this
Copy
Rclla Oaplx
Crack it: I don’t know the key
Tries every key and ranks the results by how English they read
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Step by step
How each letter is worked out by hand
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Letter frequencies
Count the letters and compare them with English
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Which cipher is this?
A guess from the text’s letters and symbols
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