Thread Identification Chart (American Standard)

Basic Major DiameterThreads Per Inch
InchmmUNCUNFUNEFUNM
.01180.30    
.01180.30   318
.01380.35   282
.01460.37    
.01570.40   254
.01650.42    
.01770.45   254
.01890.48    
.01970.50   203
.02090.53 160  
.02130.54    
.02170.55   203
.02360.60   169
.02440.62    
.02760.70   145
.03110.79    
.03150.80   127
.03400.86 120  
.03540.90   113
.03941.00   102
.04331.10   102
.04701.19 9096 
.04721.20    
.05121.30    
.05511.40   85
.05911.50    
.06001.52 80  
.06291.60    
.06691.70    
.07091.80    
.07301.856472  
.07481.90    
.07872.00    
.08602.185664  
.08662.20    
.09062.30    
.09842.50    
.09902.514856  
.10242.60    
.11022.80    
.11202.844048  
.11813.00    
.12503.184044  
.12603.20    
.13803.503240  
.14173.60    
.15754.00    
.16144.10    
.16404.173236  
.17724.50    
.18504.70    
.18754.76    
.19004.832432  
.19695.00    
.20875.30    
.21605.49242832 
.21655.50    
.21885.56    
.23626.00    
.25006.35202832 
.27567.00    
.28127.14    
.31257.94182432 
.31257.94   27
.31508.00    
.35439.00    
.37509.53162432 
.38309.73    
.393710.00    
.405010.29   27
.433111.00    
.437511.11142028 
.472412.00    
.500012.70132028 
.518013.16    
.540013.72   18
.551214.00    
.562514.29121824 
.625015.88111824 
.629916.00    
.656016.66    
.675017.15   18
.687517.46  24 
.708718.00    
.750019.05101620 
.787420.00    
.812520.64  20 
.825020.96    
.840021.34   14
.866122.00    
.875022.2391420 
.902022.91    
.937523.81  20 
.944924.00    
1.000025.4081420 
1.023626.00    
1.04101126.44    
1.050026.67   14
1.062526.99  18 
1.063027.00    
1.125028.5871218 
1.181130.00    
1.187530.16  18 
1.189030.20    
1.250031.7571218 
1.259832.00    
1.299233.00    
1.309033.25    
1.312533.34  18 
1.315033.40   11 1/2
1.375034.9361218 
1.378035.00    
1.417336.00    
1.437536.51  18 
1.492037.90    
1.496138.00    
1.500038.1061218 
1.535439.00    
1.562539.69  18 
1.574840.00    
1.625041.28  18 
1.650041.91    
1.653542.00    
1.660042.16   11 1/2
1.687542.86  18 
1.745044.32    
UNC-Unified National Course
UNF-Unified National Fine
UNEF-Unified National Extra Fine
UNM-Unified National Miniature
NPT-National Pipe Tapered

*All information is strictly informative