Seed Bead Sizes

The unit of measurement for seed beads is known as 'Aught' which is either displayed as a symbol ' ° ' or a forward stroke followed by a 0. The number that precedes this refers to the beads size. The larger the number is, the smaller the bead. The most commonly used seed bead size is 11/0 ("eleven-aught"), but sizes can range anywhere from from 24/0 to 1/0. The term "aught" refers to how many beads can fit into a standard unit, although this size can vary between manufacturers.

Aught size	Diameter in mm	Beads per Inch	Beads Per Gram
1/0	6.5	3	3
2/0	6	5	5
3/0	5.5	6	8
6/0	4	10	12
8/0	3.1	13	40
9/0	2.7	14	60
10/0	2.3	15	80
11/0	2.1	17	100
12/0	1.9	18	130
13/0	1.7	20	160
14/0	1.4	21	220
15/0	1.3	23	250
delica/treasure	1.8	20	100

* Please Note
This chart is a guide only, sizes will vary between manufacturers and depending on the finishes applied. For example a transparent size 11 bead will be smaller than a permanent galvanised size 11. This is due to the extra coatings applied throughout the manufacturing process to achieve a variety of finishes.

Colors and Finishes

Seed beads not only come in a range of colours but they also have a wide variety of finishes as well. Some beads may have more than one finish applied to create even more variations. The colour of a seed bead refers to the original colour of the glass used to create the bead, and the finish is applied to the surface or the core of the bead.

• Transparent - The bead is see-through allowing light to pass directly through the glass
• Translucent or Milky - A diffused light can be seen through the bead 
• Opaque - The solid color prevents light from passing through the bead
• Matte - A frosted finish on the bead which causes light relecting off them to be diffused
• Silver-Lined - Transparent bead that has a silver coating within the core of the bead
• Copper-Lined - Transparent bead that has a copper coating within the core of the bead
• Bronze-Lined - Transparent bead that has a bronze lining within the core of the bead
• Gold Lined - Transparent bead that has a gold lining within the core of the bead
• luster  - a shiny coating applied to the beads surface giving the bead a shiny finish like the nacre of a pearl
• Gold Lustered - The luster is created using gold dust which gives the bead a rich golden metallic hue
• AB or aurora borealis -  a rainbow effect applied to the surface of a seed bead. The effect is similar to the iridescence that can be seen on soap bubbles
• Color Lined beads are transparent beads that have had an opaque color applied to the inside of the bead
• Metallic beads have been heated and then sprayed with oxidized tin. The thicker the coating, the darker the finish.
• Higher Metallic beads are surface coated with gold and then sprayed with oxidized titanium. The gold provides a brighter finish to these beads.
• Iris - This finish gives an 'oil slick' appearance, giving the beads purple/teal/blue/fuschia tones. This finish is generally used on dark rich tones such as purple, brown blue and green.
• Ceylon - A pearl Lustered finish. These beads generally come in pale pastel colours and have a pearlized finish
• Galvanized The beads are plated with zinc which gives them a metallic finish. However this is not a stable finish and can rub away with friction
• Dyed - These beads are transparent beads that have been painted and baked. Strong UV light may cause fading over time.