String distance calculators

Also sometimes known as edit distance. Quantifying the difference between two strings is useful for a number of applications in information theory, linguistics, and computer science. There are three main algorithms:

Levenshtein distance

Levenshtein distance is the number of single-letter insertions, deletions or substitutions required to change one string into the other.

Damerau-Levenshtein distance

Damerau-Levenshtein distance is like Levenshtein distance, but also allows transpositions. The Damerau-Levenshtein distance between goat and gaot is therefore 1: the one transposition of o with its neighboring a).

Hamming distance

Hamming distance uses only substitutions when calculating the number of operations needed to change one string into the other: no deletions, insertions, or transpositions. The two strings given to the Hamming distance algorithm must therefore be of equal length.