I often have people ask me how many beads are in a tube of seed beads, so here is the approximate number of seed beads in a gram.

Round
size 15/0 : 290
size 11/0 : 110
size 8/0 : 40
size 6/0 : 12

Cylinder (Delicas)
11/0 : 200

Cubes
4MM cubes: 12
3MM cubes:

Drops
3.4 mm: 20

Super Duo: 13

Our 15s and Delicas are in 10 gram tubes, and the other beads are in the larger tube, 22 - 24 grams for most sizes and shapes.

So how many beads will it take to make that necklace? Here's the approximates number of beads per inch for seed beads:

Round
Size 15/o : 24
Size 11/o : 18
Size 8/o : 13
Size 6/o : 10

Cylinder (Delica)
Size 11/o : 20

Cube
4mm : 6
3mm : 8.5

So if you have a tube of 8/o seed beads in a 22 gram tube, here's the math:

40 beads x 22 grams = 880 / 13 = 67.69 inches!