Standard Wire Gauge (SWG) to Millimeter Conversion Chart

Gaugemm DiameterCommon Uses 
8g.4 
9g. 3.5 
10g.3Welded mesh (50mm aperture):
– Security fencing, strong garden fencing
– large-dog enclosures
12g.2.5Welded mesh (50 mm aperture):
– Security fencing, garden fencing
– large-dog enclosures, sheep, deer & goat fencing
14g.2Welded mesh (25mm – 50mm aperture):
– Garden fencing
– medium-dog enclosures, fox, sheep, deer, goat fencing
15g.1.8 
16g.1.6Welded mesh (13mm – 25mm aperture):
– Small bird aviaries, pet rabbit runs etc.
Welded mesh (13mm– 20mm aperture):
– Rodent cages and parakeet aviaries
Welded mesh (25mm aperture):
– Cat enclosures, squirrel protection, tree guards
Welded mesh (50mm aperture):
– Garden fencing. Small-dog enclosures
17g.1.4 
18g.1.2Chicken wire (31mm aperture):
– Poultry enclosures, rabbit protection
Welded mesh (13mm – 25mm):
– Small bird aviaries, pet rabbit runs etc.
19g.1Chicken wire (50 mm aperture):
– Poultry enclosures.
Rabbit netting can (31 mm aperture):
– Rabbit protection
Welded mesh you (13mm – 25mm aperture):
– Small bird aviaries, pet rabbit runs etc.
20g.0.9Chicken wire (25mm aperture:
– Poultry enclosures, roof thatching, loft insulation 
21g.0.8 
22g.0.7Chicken wire help (13mm aperture):
– Poultry enclosures, fruit cages
Fine welded or woven mesh:
– Rodent protection, wild bird feeders
23g.0.6Fine Stainless woven mesh:
– Material and chemical filtration
25g.0.5Fine Stainless woven mesh:
– Material and chemical filtration