Metaphone

Metaphone is a phonetic algorithm for indexing words and phrases according to their sound in the English language.

Metaphone was developed by Lawrence Philips in response to the very rough differentiation of the Soundex algorithm. It is more accurate than Soundex, because it focuses more on the English pronunciation. Unlike Soundex, in which words character by character encoding, the metaphone method, the encoding of strings and their position within a word depends on. Metaphone algorithm generates variable-length codes, which are identical for similar sounding words or phrases.

Metaphone is implemented as a built-in function in a number of systems, including newer versions of PHP.

Lawrence Philips developed later with Double Metaphone an improved variant with more accurate results.