The standard grips this chord is usually shown with.
Eadd9 is E, G#, B and F#, a add nine. The shape this page opens on is written 022102, lowest string first.
Note by note. E is the root, G# is the major third, B is the fifth and F# is the ninth.

Also written E(add9), Eadd2 or E add nine. The same chord either way; which spelling you meet depends on who wrote the chart.
There are 6 common shapes for Eadd9 on the guitar, and 23 derived voicings in 2 families.
One note away. Change a single note of Eadd9 and you have E (with one note taken away), Esus2 (with one note taken away), Esus2sus4 (with one note moved), Emaj7 (with one note moved), Emaj9 (with one note added) or E6 (with one note moved).
In which keys. Every note of Eadd9 belongs to C# minor (the ♭III), E major (the I), F# minor (the ♭VII), Ab minor (the ♭VI), A major (the V) and B major (the IV).
The common shapes, written lowest string first: 022102, xx21x2, x76474, x76x77, 12-11-x-11-12-12, x-x-14-13-12-14.
Under the hand. 1 of the 6 shapes here sits in open position, and the first uses 2 open strings. 3 of the 6 need a barre. Together they cover the neck from the 1st fret to the 14th.
Drop 2. A close-position chord with the second voice from the top lowered an octave. Sits on four adjacent strings. Eadd9 has xx2102, 2221xx, xx4454, x9999x, x-x-14-13-12-14, 14-14-14-13-x-x, x2415x, 4744xx.
Drop 3. The third voice from the top lowered an octave. The dropped voice becomes the bass, which is why a string is skipped. Eadd9 has 2x210x, x2x152, x7x474, 4x445x, 7x697x, x9x997, 12-x-9-11-9-x, x-11-x-11-12-12.
What kind of chord this is. Eadd9 is a major chord — root, major third, fifth. major chords on every root, and what they are for.
The common shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.