Below is a conversion chart that converts sheet metal gauge numbers into metal thickness. 26 gauge24 ga.22 ga.20 ga .18 ga.16 ga.14 ga.13 ga.12 ga.11 ga.10 ga.9 ga.8 ga.7 ga.6 ga. .018".024".030".036".048".060".075".090".105".120".135".150".164".180".194 ...