How Do I Select a Marker Size?

Wire Gauge Chart
Brady offers a variety marker sizes for your wire marking needs. Please view the charts listed below to assist you in choosing the minimum recommended label height for your specific type of wire or cable that you are identifying.

Type THW Wire O.D.

Size
AWG.
O.D.
mm (inch)
Circumference
mm (inch)
Minimum Rcommended
Label Height
mm (inch)
18 2.74 (0.108) 2.64 (0.34) 12.70 (0.500)
16 3.00 (0.118) 9.42 (0.37) 12.70 (0.500)
14 4.11 (0.162) 12.91 (0.51) 19.05 (0.750)
12 4.55 (0.179) 14.29 (0.56) 25.40 (1.000)
10 5.05 (0.199) 15.86 (0.63) 25.40 (1.000)
8 7.01 (0.276) 22.01 (0.87) 38.10 (1.500)
6 8.20 (0.323) 25.75 (1.02) 38.10 (1.500)
4 9.45 (0.372) 29.67 (1.17) 44.45 (1.750)
3 10.19 (0.401) 32.00 (1.26) 50.80 (2.000)
2 11.00 (0.433) 34.54 (1.36) 50.80 (2.000)
1 12.90 (0.508) 40.51 (1.60) 63.50 (2.500)
1/0 13.95 (0.549) 43.80 (1.72) 63.50 (2.500)
2/0 15.11 (0.595) 47.45 (1.87) 76.20 (3.000)
3/0 16.43 (0.647) 51.59 (2.03) 76.20 (3.000)
4/0 17.91 (0.705) 56.24 (2.21) 88.90 (3.500)

Type THHN Wire O.D.

Size
AWG.
O.D.
mm (inch)
Circumference
mm (inch)
 
Minimum Recommended
Label Height
mm (inch)
 
18 2.26 (0.089) 7.10 (0.28) 12.70 (0.500)
16 2.54 (0.100) 7.98 (0.31) 12.70 (0.500)
14 2.67 (0.105) 8.38 (0.33) 12.70 (0.500)
12 3.10 (0.122) 9.73 (0.38) 12.70 (0.500)
10 3.89 (0.153) 12.21 (0.48) 19.05 (0.750)
8 5.54 (0.218) 17.40 (0.68) 25.40 (1.000)
6 6.53 (0.257) 20.50 (0.81) 31.75 (1.250)
4 8.33 (0.328) 26.16 (1.03) 38.10 (1.500)
3 9.04 (0.356) 28.39 (1.12) 44.45 (1.750)
2 9.86 (0.388) 30.96 (1.22) 50.80 (2.000)
1 11.43 (0.450) 35.89 (1.41) 57.15 (2.250)
1/0 12.47 (0.491) 36.16 (1.54) 63.50 (2.500)
2/0 13.64 (0.537) 42.83 (1.69) 63.50 (2.500)
3/0 14.94 (0.588) 46.91 (1.85) 69.85 (2.750)
4/0 16.41 (0.646) 51.53 (2.03) 76.20 (3.000)

Type PVC Wire O.D.

Size
AWG.
O.D.
mm (inch)
Circumference
mm (inch)
Minimum Recommended
Label Height
mm (inch)
22 1.57 (0.062) 4.93 (0.19) 7.62 (0.300)
20 1.75 (0.069) 5.50 (0.22) 7.62 (0.300)
18 2.00 (0.079) 6.28 (0.25) 12.70 (0.500)
16 2.34 (0.092) 7.53 (0.29) 12.70 (0.500)
14 3.50 (0.138) 10.99 (0.43) 19.05 (0.750)
12 4.01 (0.158) 12.59 (0.50) 19.05 (0.750)
10 4.65 (0.183) 14.60 (0.57) 25.40 (1.000)
8 6.35 (0.250) 19.94 (0.79) 31.75 (1.250)

Type Teflon Wire O.D.

Size
AWG.
O.D.
mm (inch)
Circumference
mm (inch)
Minimum Recommended
Label Height
mm (inch)
22 1.52 (0.060) 4.77 (0.19) 7.62 (0.300)
20 1.73 (0.068) 5.43 (0.21) 7.62 (0.300)
18 2.01 (0.079) 6.31 (0.25) 12.70 (0.500)
16 2.26 (0.089) 7.10 (0.28) 12.70 (0.500)