The standard grips this chord is usually shown with.
B11 is B, F#, A, C# and E, a dominant eleventh. The shape this page opens on is written x21200, lowest string first.

Also written B9sus4 or B dominant 11. The same chord either way; which spelling you meet depends on who wrote the chart.
There are 6 common shapes for B11 on the guitar, and 61 derived voicings in 4 families.
In which keys. Every note of B11 belongs to C# minor (the ♭VII), D major (the vi), E major (the V), F# minor (the iv), A major (the ii) and B minor (the i).
The common shapes, written lowest string first: x21200, x22242, x64455, 777877, 9-9-9-9-10-11, x-14-13-14-12-12.
Drop 2. A close-position chord with the second voice from the top lowered an octave. Sits on four adjacent strings. B11 has x2222x, 2222xx, xx2202, xx4455, xx7657, 7776xx, 7979xx, xx7977.
Drop 3. The third voice from the top lowered an octave. The dropped voice becomes the bass, which is why a string is skipped. B11 has x2x220, 5x242x, x2x252, 2x220x, x4x455, x7x475, 5x445x, 7x765x.
Rootless. The root left to the bass player. Frees a finger for a tension. B11 has xx2222, xx4655, x7767x, xx7979, x-9-11-9-10-x, x-x-11-11-10-12, x-x-14-14-14-14, x4425x.
Open string. An open string left ringing against a fretted grip. Because it costs no finger, it sounds a note the closed shape has none left for -- a tension on top, or a pedal root underneath. Either a familiar grip with open strings added, or a shape so sparse the open strings carry the chord. These belong to their key rather than to a shape, so D, A, G and E have many and Eb a handful. B11 has 00460x, x04600, 0044xx, 007600, xx4200, 0x420x.
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.