Seed bead describes a small bead type; glass describes a material. Many seed beads are glass. They are not mutually exclusive alternatives, so choose by the project’s dimensions and technique rather than treating seed and glass as opposite categories.

The useful comparison

Project What matters most
Patterned bead weaving Consistent bead shape, size and enough hole space for repeated thread passes
Bead embroidery Shape, hole position and how the beads sit against the backing
A simple strung necklace Weight, spacing, hole diameter and compatibility with the chosen cord
Matching a previous batch Exact manufacturer, shape, size and colour/finish code

A larger glass round can be easier to handle on a simple cord than a tiny seed bead. That does not make it a substitute in a pattern calculated around uniform seed beads. A size number also does not establish the same dimensions across every shape and brand.

Check a sample before buying in bulk

Try the intended needle and thread through several beads, including the number of passes required by the technique. Inspect a short stitched section against the pattern dimensions. A compatible hole in one bead is not proof that a mixed bargain pack will work consistently.

Read the maker’s care guidance for plated, dyed or coated finishes if the item will see water, friction or skin products. Do not assume a coating has the durability of the underlying glass.

Use the bead measurement guide to check dimensions and the bead quantity calculation to estimate a simple strand. Those calculations do not replace a weaving pattern’s quantities or account automatically for every clasp and spacer.