Cryptogram Helper User Instructions

The cryptotogram consists of an encoded message where each letter of the alphabet has a code letter that has been substituted. Punctuation marks and space are preserved as in the original message. The cryptogram helper provides word choices based on word length, repeated letter patterns, known or partially known letters, letter frequency, and word frequency.

To illustrate how the various strategies work suppose the encoded message contains the two words "XSDX  OTJOKT".

Word Length: The first word is lenth four so use the W4 tab to select the four letter words. For the second word use the W6 tab to select the six letter words.

Repeated Letters: The repeat pattern code is determined as follows--assign 0 to all the letters that do not repeat (S and D for XSDX, J and K for OTJOKT), assign 1 to the left most letter that repeats (X in XSDX, O in OTJOKT) and to all of its repetitions, assign 2 to the left most of the remaining letters (T in OTJOKT) and all of its repetitions, continue on assigning digits to the letters until all the letters have been assigned a digit. The resulting number is called the letter repetition pattern (LRP). For XSDX the LRP is 1001, for OTJOKT the LRP is 120102.

In the pulldown menu under the "pat" column choose the LRP to select only those word matching the letter repetition pattern. For XSDX this yields the ten words: area, dead, died, edge, else, high, noun, says, test, and that. For OTJOKT this yields the three words: indian, people, and proper.

Known and Partially Known Letters: If some letters are known or even if partial information about some letters is known that can also be used. For example suppose it is known that D is the code letter for a. (This type of information happens when the original message has occurances of the single letter words a and I.) For XSDX (on the W4 sheet) choose the third letter pulldown menu ( column E) and choose a. That together with the repeated letters choice narrows down to the two words "dead" or "that". Suppose it is known that O is not the code letter for i. For OTJOKT (on the W6 sheet) choose the first letter pulldown menu (column C) choose custom, does not equal, and i. That narrows the possible words to "people" or "proper" and strongly suggest that O is the code letter for p.

Letter Frequency: Letter frequency is based on categorizing letters into 9 frequency categories. 1 is the highest frequency and 9 is the lowest. Letter assignments to frequency categories is as follows 1-e, 2-t, 3-aixnos, 4-hr, 5-dl, 6-cmu, 7-fpq, 8-yvwb, 9-gjkxz. The idea is that if a particular code letter say X is the second most frequently occurring letter in the entire coded message then it is more likely to be a 't' than a 'd', i.e. "that" is more likely that "dead" for XSDX.

Word Frequency: The word frequency column (column B) indicates the frequency order for the first five hundred English words. So for example "that " is number 9 (ninth most frequent word in English) and "people " is number 80.