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What is Soundex?

The Soundex Algorithm
The term "Soundex" is a generic term that covers many variations of an algorithm for categorizing (not searching) names that was first patented in 1918 by Robert Russell.

Most variations work in the same way. They convert the name into a code consisting of the first letter, followed by several numbers that are assigned based upon a pre-determined grouping of consonants.

Soundex codes begin with the first letter of the surname followed by a three-digit code that represent the first three remaining consonants. Zeros will be added to names that do not have enough letters to be coded.

Soundex Coding Guide (Consonants that sound alike have the same code)
1 - B,P,F,V
2 - C,S,G,J,K,Q,X,Z
3 - D,T
4 - L
5 - M,N
6 - R
The letters A,E,I,O,U,Y,H, and W are not coded.

Names with adjacent letters having the same equivalent number are coded as one letter with a single number. Surname prefixes such as La, De and Van are generally not used in the soundex. Mc, Mac and O generally are not considered prefixes for soundex.

Soundex Warning
There are, as with most things, some anomalies and limitations. For more detailed information please use a search engine or start here:
http://www.searchforancestors.com/soundex.html
http://en.wikipedia.org/wiki/Soundex

To Calculate a Soundex Code by Hand:

1) Print name. (i.e. Atkins)
2) Cross out spaces, punctuation, accents and other marks
3) Cross out any of the following characters A, E, I, O, U, H, W, Y (unless first letter of surname) (i.e. Atkns)
3) Cross out the second letter of duplicate characters
4) Cross out the second letter of adjacent characters with the same soundex number.
5) Convert characters in positions 2 to 4 to a number using the following numbers
Fill any unused positions with zeros e.g.. Lee is L000, Bailey is B400.

There is always one letter followed by 3 numbers.

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