Always use uppercase letters for chord and note names.
Use "#" to identify a sharp note (ex. C Sharp would be entered as "C#").
Use "b" to identify a flat note (ex. E Flat would be entered as "Eb").
Use "+" and "-" to show a modified chord extension. For example, an Eb diminished chord would be written as "Eb-5". A Bb7 Sharp 9 chord would be written as "Bb7+9".
Use "/" to identify an alternate bass note (otherwise known as a slash chord; ex. "F/A" is an F major chord over an A).
Only chord extensions up to "13" are supported.
White space (extra spaces) should be avoided, if possible.
Just about every chord you can think of should be supported, but please contact me if you run across a chord that is not.
Examples
C augmented = "Caug" or "C+" or "C+5".
Eb no third (a.k.a. - a power chord) = "Eb no 3rd" or "Ebno3", etc.
F over G = "F/G"
Bb suspended = "Bbsus"
A half-diminished 7th = "Amin7-5" (There is no easy way to type the normal half-diminished symbol, "ø", so it is not supported).
G fully-diminished 7th = "Go7" or "Gdim7"
D-sharp 9th = "D#9"
D augmented 9th (implies that the 7th is included, too) = "D+9"
D-sharp augmented 9th = "D#+9"
D major with an added sharp 9 (intentionally omitting the 7th) ="D add +9"
You can make odd combinations, too, such as: "E11-9+5/Gb". That doesn't mean that it will sound good, but it is a theoretical possibility!
