Please note that the information here is only a guide for jewellery wire but may be relevant to other industries as well.  

Wire Gauge Standards.....sort of.....

Gauge refers to the width of the jewellery wire (also called the diameter).  The higher the gauge number, the thinner the jewellery wire.  So 14 gauge jewellery wire is thicker than 20 gauge jewellery wire (14ga also costs more too!).

There are two Jewellery wire gauge standards available:-

1.  The American standard - called the B&S gauge (Brown and Sharpe) or the AWG (American Wire Gauge).

2.  The British version - called the SWG (Standard Wire Gauge).

We Australian's usually use the American version but not all of the time.  Some shops don't tell you which standard they are using so the best thing to do is find out the exact measurement of the wire and work it out yourself.   Hence the reason for the table below :-)  If they quote the size in inches, use the table to convert it to mm.

All information on this site uses the B & S standard (i.e. the American one).

Below is a table that shows the measurements for B &S Gauge & SWG; I've even put the millimetre conversions in there so you can make a little more sense of it.

Just so that you know, here are the base measurements to use for converting feet to metres and inches to millimetres.

25.4 mm = 1 inch
30.48cm = 1 foot
1 m = 3.3 feet

 

  SWG (British) B & S Gauge (American)
Wire
Gauge
Size in Inches Size in MM Size in Inches Size in MM

6

0.192

4.8768

0.1620

4.1150

8

0.16

4.064

0.1285

3.264

10

0.128

3.2512

0.1019

2.5880

12

0.104

2.6416

0.0808

2.052

14

0.08

2.032

0.0641

1.68

16

0.064

1.6256

0.0508

1.29

18

0.048

1.2192

0.0403

1.02

19

0.04

1.016

0.0359

0.9119

20

0.036

0.9144

0.032

0.81

21

0.032

0.8128

0.0285

0.72

22

0.028

0.7112

0.0253

0.64

24

0.022

0.5588

0.0201

0.51

26

0.018

0.4572

0.0159

0.40

28

0.0148

0.37592

0.0126

0.32

30

0.0124

0.31496

0.01

0.25

32

0.0108

0.27432

0.008

0.2032

34

0.0092

0.23368

0.0063

0.1601

 

Please remember that this is for information purposes only and it is only a guide.

As with everything these days, there is a tolerance to consider. So an 18ga wire (1.02mm) may be just less (0.96mm for example) or just a little thicker (1.1mm) which is acceptable. All wire is manufactured so depending on where it's made and what the quality is like will determine how close to the standard it is. Some people disagree with this, but I have seen differences between batches, it is just something to keep in mind. The better the quality of the wire usually, the more correctly sized it is.

 

Wire by Weight

Wire can be sold by weight which is a little daunting at first. I have made it easy on my site as I sell all wire by length as this makes more sense to me. So below are two tables that summarise the most common jewellery wire gauges available for Sterling Silver (and Argentium) wire and Gold Filled wire and how many feet (Ft) and metres (M) you get per troy ounce (Ozt) weight of wire.

I have put the American troy ounce measurements in, as the jewllery wire is usually sold by the foot or the troy ounce (American measurements are still not yet metric!). Be aware that there are different shapes and different shapes have different weights; therefore you get a different amount when using weight as the form of measurement. If the table detail is blank, then I could't find the conversions.  Here are some handy conversion details for you:-

1 Ounce = 28 grams
1 Troy Ounce = 31 grams

 

Table 1:- How much Gold Filled Wire you get per Troy ounce.....

 
GF Round

GF Half  Round

GF Square
Wire
Gauge

Ft/Oz*

M/Oz*

Ft/Oz*

M/Oz*

Ft/Oz*

M/Oz*

6

 

 

1.74

0.53



 

8

 

 

2.57

0.78

 

 

10

 

 

3.96

1.21

 

 

12

2.16

0.66

6.97

2.21

 

 

14

5.45

1.66

10.84

3.30

4.29

1.31

16

8.65

2.64

17.82

5.43

6.81

2.08

18

13.8

4.21

27.91

8.51

11

3.35

19

17.54

5.35

 

 

 

 

20

21.68

6.61

42.87

13.07

15.95

4.86

21

27.59

8.41

59.82

18.23

20.93

6.38

22

35.55

10.84

62.5

19.05

25.92

7.9

24

56.33

17.17

112.66

34.34

41.87

12.76

26

83.33

25.4

 

 

68.76

20.96

28

140.77

42.91

 

 

110.84

33.78

30

223.71

68.19

 

 

176.15

53.69

 

Table 2:- How much Sterling Silver (Argentium) Wire you get per Troy ounce.....

 


SS Round


SS Half  Round

SS Square


Wire
Gauge


Ft/Ozt*

M/Ozt*

Ft/Ozt*

M/Ozt*

Ft/Ozt*

M/Ozt*

6

0.75

0.23

1.5

0.46

0.63

0.19

8

1.21

0.37

2.33

0.71

0.92

0.28

10

1.83

0.56

3.75

1.14

1.5

0.46

12

3

0.91

6

1.83

2.25

0.69

14

4.66

1.42

9.5

2.9

3.75

1.14

16

7.5

2.29

15

4.57

6

1.83

18

12

3.66

24

7.32

9.5

2.9

20

19

5.79

38

11.58

15

4.57

21

24

7.32

50

15.24

18.79

5.73

22

31

9.45

62

18.9

24

7.32

24

48

14.63

96

29.26

36

10.97

26

76

23.16

 

 

59.96

18.28

28

121.21

36.94

 

 

95.2

29.02

 

* Remember these are approximations only :-) Most jewellery wire is cut by hand so may be just over/under a troy ounce weight.  Also remember to check which "Ounce Weight" the seller may be using, a “normal” ounce weight (Oz) or a “troy ounce” weight (Ozt), the tables above are Troy Ounces which is heavier.