Metric Conversion Chart for Jewelry Makers

Some people new to gemstones and beading have never come across the metric measuring system often used in jewelry making. Even some of us who have been at it for a long time need help figuring out just how big 11mm is.
Dr Karen Meador made this chart to help with these conversions.

Conversion of Units

25.4 millimeters (mm) = 1 inch

1 millimeter is less than 1/16 inch

To Convert Inches to Millimeters: Multiply Inches x 25.4

To Convert to Millimeters to Inches: Multiply millimeters x .03937

Conversion Chart: Millimeters to Inches

Mm	Inches in Decimals	*Inches in Fractions
1mm	0.04 inches	Less than 1/16 inch
2mm	0.08 inches	Greater than 1/16 inch & less than 1/8 inch
3mm	0.12 inches	Greater than 1/16 inch & less than 1/8 inch
4mm	0.16 inches	Greater than 1/8 and less than 3/16
5mm	0.2 inches	Greater than 3/16 and less than 1/4
6mm	0.24 inches	Greater than 3/16 and less than 1/4
7mm	0.28 inches	Greater than ¼ and less than 5/16
8mm	0.32 inches	Greater than ¼ and less than 5/16
9mm	0.35inches	Greater than 5/16 and less than 3/8
10mm	0.40 inches	Greater than 3/8 and less than 7/16
12mm	0.47 inches	Greater than 7/16 and less than 8/16
14mm	0.55 inches	Greater than ½ and less than 9/16
16mm	0.63 inches	Greater than 5/8 & less than 11/16
18mm	0.71 inches	Greater than 11/16 and less than 3/4

*The third column of this conversion chart is offered to help anyone who thinks more clearly using fractions than using decimals.

Approximate Number of Round Beads on a 16” Strand

2mm	3mm	4mm	6mm	8mm	10mm	12mm
203	136	100	67	50	41	34

Every inch is 25mm so times the number of inches by 25mm and you have how long the strand is in millimeters. Then divide by the width of the bead.

Note: Copied with the permission of:
Karen Meador
Dream Catcher Designs