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Substitution cipher

Please note that these tools aren't optimized for large amounts of data, processing can slow down or run into problems once you reach above 150,000 characters. A cap of 1 million characters is currently in place.

A substitution cipher uses a key or a phrase to make a new alphabet, with the end result potentially being a completely jumbled up alphabet.

A quick example substitution: WORLD → HELLO → WNRJO - The full alphabet would look like HELOABCDFGIJKMNPQRSTUVWXYZ – notice that H, E, L and O have moved to the start, the second L in HELLO isn't present again as it has already been used and placed. Mixed case strings and keys are supported here, for example: WOrld → HELLO → WNrjo or WOrld → HEllo → UMpjo – There is more information available on the Substitution cipher Wikipedia page.