Letters & Word Values

Letter frequencies, index of coincidence, word values in several schemes, and anagram checking.

The text

What kind of cipher is it

Index of coincidence
Letters counted

Bars are the text; the notches are what English would give.

Best Caesar shifts

Scored on letter frequencies alone. For a fuller ranking, and every other cipher at once, use Decode Anything.

    Word values

    Word A=1 A=26 Scrabble ASCII

    Anagram check

    Verdict
    Letters still needed
    Letters left over

    This checks a guess rather than generating one: there is no dictionary behind it, because shipping a word list would be a megabyte of download for a job the rest of the site does not need.

    Read the index of coincidence first

    It is the single most useful number on this page, and it answers the question you actually have: is this worth brute-forcing? It is the chance that two letters picked at random from the text are the same one. English sits around 0.067; a flat, evenly spread distribution sits around 0.038.

    A simple substitution (Caesar, Atbash, pigpen, a keyed alphabet) only renames the letters. E becomes X, but it's still the commonest letter, so the index barely moves. A high index therefore means the letters have merely been swapped about, and frequency analysis will get you there. A low one means something like Vigenère has spread each plaintext letter across several cipher letters, and no amount of staring at a frequency chart will help. You need the keyword.

    Short texts are noisy. Under about fifty letters the index bounces around enough to mislead, so treat it as a hint rather than a verdict, and lean on the ranked decodings instead.

    Word values

    “Take the value of the church name” almost always means A=1, B=2 and so on, and almost always wants the total rather than the digits. The other columns are here for the puzzles that say otherwise: reversed values turn up occasionally, Scrabble scores rather less often, and an ASCII total is usually a sign the cache owner is a programmer.