How many 2, 3, 4, 6 and 8 mm beads do I need?
Counts below assume finished lengths of 18 or 24 inches as noted, a 1.5 inch clasp allowance on 18, and beads touching. We round to whole beads.
- 18 in (with 1.5 in clasp): 4 mm about 104. 6 mm about 70. 8 mm about 52.
- 24 in fully beaded (no clasp, IGS): 2 mm 300. 3 mm 200. 4 mm 150. 6 mm 99. 8 mm 75.
- For 20 in and 30 in, use the one-line formula below with beads per inch: 2 mm 12.5, 3 mm 8.3, 4 mm about 6.3, 6 mm 4.2, 8 mm about 3.2.
- If your clasp length differs, replace 1.5 in with its actual length when you apply the formula.
What formula should I use?
We subtract 1.5 inches for clasp and findings, then multiply the beaded run by beads per inch. Use 25.4 mm per inch if you prefer working in millimeters. For beads per inch, we use 2 mm 12.5 and 3 mm 8.3 (IGS), plus 4 mm about 6.3, 6 mm 4.2, 8 mm about 3.2 from our shop and trade math.
Rondelles are the workhorse for stringing. See how they are sized and drilled on our rondelles page.
Will one strand cover my length?
Here is how our typical 15 to 16 inch rondelle strands line up with the counts above. Jaipur-cut strands also come in 13 inch; for those, plan extra or combine with spacers.
- 2 to 3 mm strands carry high bead counts. They cover 18 inches and often 20 inches. Longer runs benefit from two strands or spacer design.
- 4 mm strands have about 95 to 100 beads. 18 in needs about 104, so use two strands or add spacers or a focal. Lengths past 18 in call for two strands.
- 6 mm strands have about 65 to 70 beads. 18 in usually fits one strand. Longer lengths need two strands.
- 8 mm strands have about 48 to 52 beads. 18 in may need a couple extra beads, so plan two strands or add spacers. Longer lengths need two strands.
How many 6 mm beads do I need?
Plan about 70 for 18 in. One 15 to 16 inch strand of 6 mm rondelles usually covers 18 inches with a standard clasp.
Tara here: we keep a small tray of extra 6 mm rondelles to top up a strand when a clasp eats less than 1.5 inches or a focal shifts the count.
Does spacing or knotting change my count?
Yes. Each knot or tiny spacer adds length, so you need fewer beads for the same finished size. A simple rule we use: budget about 1 mm of added length per knot.
To adjust, calculate the beaded run in millimeters, subtract total knot length, then divide by bead size in mm. For rondelles listed 4x3 mm, use the height on the string for this math.
What stones do these counts fit?
Use the same counts for gemstone rondelles across stones, then choose your color story. For neutrals with flash, see our labradorite guide. For February lines, our amethyst guide covers grades and care.
We cut multi tourmaline in small rondelles for color-forward strands. If you prefer to shop in person, our current InterGem dates are on the show schedule.