Daitch-Mokotoff Soundex Rules

The Daitch-Mokotoff Soundex System was created by Randy Daitch and Gary Mokotoff of the Jewish Genealogical Society because they concluded the system developed by Robert Russell in 1918, and in use today by the U.S. National Archives and Records Administration (NARA) does not apply well to many Slavic and Yiddish surnames. It also includes refinements that are independent of ethnic considerations. The rules for converting surnames into D-M Code numbers are listed below. They are followed by the coding chart.

1. Names are coded to six digits, each digit representing a sound listed in the coding chart (below).
2. When a name lacks enough coded sounds for six digits, use zeros to fill to six digits. GOLDEN which has only four coded sounds [G-L-D-N] is coded as 583600.
3. The letters A, E, I, O, U, J, and Y are always coded at the beginning of a name as in Alpert 087930. In any other situation, they are ignored except when two of them form a pair and the pair comes before a vowel, as in Breuer 791900 but not Freud.
4. The letter H is coded at the beginning of a name as in Haber 579000 or preceding a vowel as in Manheim 665600, otherwise it is not coded.
5. When adjacent sounds can combine to form a larger sound, they are given the code number of the larger sound. Mintz which is not coded MIN-T-Z but MIN-TZ 664000.
6. When adjacent letters have the same code number, they are coded as one sound, as in TOPF, which is not coded TO-P-F 377000 but TO-PF 370000. Exceptions to this rule are the letter combinations MN and NM whose letters are coded separately, as in Kleinman, which is coded 586660 not 586600.
7. When a surname consists or more than one word, it is coded as if one word, such as Ben Aron which is treated as Benaron.
8. Several letter and letter combinations pose the problem that they may sound in one of two ways. The letter and letter combinations CH, CK, C, J, and RS are assigned two possible code numbers.