by Robyn, Exclusively for Fire Mountain Gems and Beads®

Do you wonder where the measurement for each bead comes from? Do you ponder over how many beads are on each strand? Do you contemplate whether you are getting the most out of your strands? Well, now there is no more deliberating! The following charts and illustrations offer at-a-glance information from accurately identifying the number of beads available on each strand to how many beads it will take to create necklaces of varying lengths.

Beads per Inch Chart

"How many beads per inch?" is one of the most commonly asked questions. The majority of beads are sold by the strand, with the most common strand length being 16 inches. The number of beads per strand varies according to bead size and strand length, which can vary from batch to batch.

For easy jewelry designing, take a look at the "Beads per Inch Chart" below. This chart shows you the approximate number of beads for various lengths and helps decipher how many beads it will take to create necklaces of varying lengths. For example, if you wanted 4mm beads and they came on a 16-inch strand, you would receive approximately 102 beads.

Beads Per Inch Chart
Inch Ruler 1" 4" 8" 12" 16" 20" 24" 28" 32"
2mm Round Beads
12.7 50.8 101.6 152.4 203.2 254 304.8 355.6 406.4
3mm 8.47 33.87 67.73 101.6 135.47 169.33 203.2 237.07 270.93
6x4mm Rondelle Beads
6.35 25.4 50.8 76.2 101.6 127 152.4 177.8 203.2
5mm 5.08 20.32 40.64 60.96 81.28 101.6 121.92 142.24 162.56
6x4mm Tube Beads
4.23 16.93 33.87 50.8 67.73 84.67 101.6 118.53 135.47
7mm 3.63 14.51 29.03 43.54 58.06 72.57 87.09 101.6 116.11
8mm Roound Beads
3.18 12.7 25.4 38.1 50.8 63.5 76.2 88.9 101.6
9mm 2.82 11.29 22.58 33.87 45.16 56.44 67.73 79.02 90.31
15x10mm Rondelle Beads
2.54 10.16 20.32 30.48 40.64 50.8 60.96 71.12 81.28
11mm 2.31 9.24 18.47 27.71 36.95 46.18 55.42 64.65 73.89
12x8mm Oval Beads
2.12 8.47 16.93 25.4 33.87 42.33 50.8 59.27 67.73
13mm 1.95 7.82 15.63 23.45 31.26 39.08 46.89 54.71 62.52
14mm Rounds Beads
1.81 7.26 14.51 21.77 29.03 36.29 43.54 50.8 58.06
15mm 1.69 6.77 13.55 20.32 27.09 33.87 40.64 47.41 54.19
16x8mm Teardrop Beads
1.59 6.35 12.7 19.05 25.4 31.75 38.1 44.45 50.8
17mm 1.49 5.98 11.95 17.93 23.91 29.88 35.86 41.84 47.81
18mm 1.41 5.64 11.29 16.93 22.58 28.22 33.87 39.51 45.16
19mm 1.34 5.35 10.69 16.04 21.39 26.74 32.08 37.43 42.78
20mm 1.27 5.08 10.16 15.24 20.32 25.4 30.48 35.56 40.64
21mm 1.21 4.84 9.68 14.51 19.35 24.19 29.03 33.87 38.7
22mm 1.15 4.62 9.24 13.85 18.47 23.09 27.71 32.33 36.95
23mm 1.1 4.42 8.83 13.25 17.67 22.09 26.5 30.92 35.34
24mm 1.06 4.23 8.47 12.7 16.93 21.17 25.4 29.63 33.87
25mm 1.02 4.06 8.13 12.19 16.26 20.32 24.38 28.45 32.51

(Bead counts per inch are approximate)

To estimate the number of beads per strand, for a bead size not shown in the chart above, follow this formula:

Just remember that 1 inch = 25.4mm. Multiply the length of the strand by 25.4, and divide by the size of the beads in millimeters.

25.4 x 16 = 406.4 Strand Length in Millimeters
406.4 ÷ 9 = 45.1 Total 9mm Beads on 16-inch Strand

Number of Beads per 16-Inch Strand

An essential tool for jewelry designers, the "Number of Beads per 16-inch Strand" is a handy chart that lists the number of beads to be expected on a 16-inch strand, according to the stringing length. For example, if you wanted a 16-inch strand of 25mm donut beads, you would receive approximately 15 beads.

How Many Beads Will You Need To Make a Necklace?

From time to time, you might ask, "How many beads will it take to design a necklace?" Well, according to each bead's shape and stringing length, the strand length you have in mind and the necklace type, here is an estimation guide of how long a necklace would be.

Type Length
Collar 14 to 17 inches
Choker 16 to 18 inches
Princess 17 to 19 inches
Matinee 20 to 25 inches
Opera 26 to 36 inches
Rope 37 inches or longer

To estimate the number of beads needed to design any of these necklaces, follow this formula:

Remember that 1 inch = 25.4mm. Multiply the length of the strand by 25.4, and divide by the size of the beads in millimeters.

Strand Length x 25.4mm (1 inch) ÷ bead millimeter = Approximate Bead Quantity Required for Design.

For example:
  1. 18-inch princess necklace made with 4mm beads: 18 x 25.4 ÷ 4 = 114.3
  2. 32-inch opera necklace made with 10mm beads: 32 x 25.4 ÷ 10 = 81.2
Since beads may be irregular, these numbers are approximate. Also, if you are knotting between the beads, add 1 or 2mm for each knot, depending on the thickness of the thread being used.

What size necklace will a 16-inch strand of beads make when knotted?

Bead Size Strand Length/Number of Beads
4mm 16'' strand, 102 beads, knotted makes 20-inch long necklace
6mm 16'' strand, 68 beads, knotted makes 18-3/4 inch long necklace
8mm 16'' strand, 51 beads, knotted makes 18-inch long necklace

Conversion of Millimeters to Inches

Easily convert millimeters to inches with the featured ''Metric Conversions''. From 1mm to 20mm, get the closest equivalent in inches in an easy-to-read, printer-friendly format. Keep the chart at your workbench or shop for quick frame of reference.

Measuring Beads

For consistency, beads are measured in millimeters with the largest number mentioned first. For example, describing a bead that is 10mm means it would be round and have an outer dimension of 10mm when measured hole-to-hole or perpendicular to the hole.

For beads with two-dimensional measurements, the order of the measurement is length by width. To make measurements consistent, Fire Mountain Gems always puts in the largest dimension first.

  • For example, 10x6mm would indicate the bead is 10mm long and 6mm wide at its widest point. For a shape like a briolette or teardrop bead, the length is the measurement from the top to the bottom (perpendicular to the string) of the bead and the width is the measurement as viewed following the hole (parallel to the string) but in the widest part of the bead.

  • For beads like the oval shape, the length is the distance from one hole to the other and the width is perpendicular to the hole, usually at its widest section.

As you use these helpful reference charts and guidelines, you will become more familiar with the amount of beads needed to create one-of-a-kind designs.

Additional Resources:

Customer Comments

We would like to share some of the customer comments we received in response to the article "How Many Beads per Strand?," as featured in an email newsletter. Please keep in mind that the comments expressed below are those of our customers and do not reflect the views of Fire Mountain Gems and Beads.

"This is wonderful - no more converting back and forth!"
- Ellen

"Excellent, something I always wanted to know but to afraid to ask and if not didn't think I would understand. Thanks."
- Sheila

"Very helpful."
- Mary

"Excellent resource. After many years of beading, I have much of this information in my head, but thank you for putting it all in one place."
- Corinne

"This was great. The charts will be very useful."
- Nancy

"This was a fantastic resource."
- Vicki

"This was very helpful! I hope you post it permanently on your website."
- Nancy

"AWESOME!! :-)"
- Ella

"Re: Bead measuring chart. This is the greatest!!! What a time saver. Makes designing and ordering so much easier. Thanks"
- Carolyn

"I was so pleased to finally find an answer to so many of my questions. Thank you."
- Marilynn

"The charts are very handy and I will laminate them collectively. Great for quick reference. Thank you FM. Jonellen Reber, customer and fm. Fan."
- Jonellen

"Thank you for putting all of these wonderful charts in one article! I know most of the info is in your catalogs, or has been in the past, but this is easier to carry around than the (beautiful, but heavy) catalog. I think this is one of the most beneficial articles I have read in this column."
- Shirley

"Your article was very helpful. I was wondering if you have a chart for knotted pearls. Especially one using different sizes of pearls ( like a graduated pearl necklace ... for a 16 or 18 inch necklace. Maybe you would know how I can figure it myself.) Thank you,"
- Joan

"This is great. I will save to my favorites to refer to often, I'm sure. I love FMG."
- Donna

"Awesome information! Thanks so much."
- Diane

"Terrific charts and very informative. Why doesn't Fire Mountain have these printed up and give as a "Gift for Shopping." It certainly would be appreciated and I am sure, used constantly."
- Lydia

"Great help, I just usually pinch hit, but will keep this for future projects."
- Patricia

- Jacklyn