Thread Identification Chart (American Standard)
| Basic Major Diameter | ||||||
|---|---|---|---|---|---|---|
| Nom Dia. | Threads Per Inch | |||||
| Inch | mm | UNC | UNF | UNEF | UNM | |
| .0118 | 0.30 | |||||
| .0118 | 0.30 | 0.30 | 318 | |||
| .0138 | 0.35 | 0.35 | 282 | |||
| .0146 | 0.37 | |||||
| .0157 | 0.40 | 0.40 | 254 | |||
| .0165 | 0.42 | |||||
| .0177 | 0.45 | 0.45 | 254 | |||
| .0189 | 0.48 | |||||
| .0197 | 0.50 | 0.50 | 203 | |||
| .0209 | 0.53 | 160 | ||||
| .0213 | 0.54 | |||||
| .0217 | 0.55 | 0.55 | 203 | |||
| .0236 | 0.60 | 0.60 | 169 | |||
| .0244 | 0.62 | |||||
| .0276 | 0.70 | 0.70 | 145 | |||
| .0311 | 0.79 | |||||
| .0315 | 0.80 | 0.80 | 127 | |||
| .0340 | 0.86 | 120 | ||||
| .0354 | 0.90 | 0.90 | 113 | |||
| .0394 | 1.00 | 1.00 | 102 | |||
| .0433 | 1.10 | 1.10 | 102 | |||
| .0470 | 1.19 | 90 | 96 | |||
| .0472 | 1.20 | 1.20 | ||||
| .0512 | 1.30 | |||||
| .0551 | 1.40 | 1.40 | 85 | |||
| .0591 | 1.50 | |||||
| .0600 | 1.52 | 80 | ||||
| .0629 | 1.60 | |||||
| .0669 | 1.70 | |||||
| .0709 | 1.80 | |||||
| .0730 | 1.85 | #1 | 64 | 72 | ||
| .0748 | 1.90 | |||||
| .0787 | 2.00 | |||||
| .0860 | 2.18 | #2 | 56 | 64 | ||
| .0866 | 2.20 | |||||
| .0906 | 2.30 | |||||
| .0984 | 2.50 | |||||
| .0990 | 2.51 | #3 | 48 | 56 | ||
| .1024 | 2.60 | |||||
| .1102 | 2.80 | |||||
| .1120 | 2.84 | #4 | 40 | 48 | ||
| .1181 | 3.00 | |||||
| .1250 | 3.18 | #5 | 40 | 44 | ||
| .1260 | 3.20 | |||||
| .1380 | 3.50 | #6 | 32 | 40 | ||
| .1417 | 3.60 | |||||
| .1575 | 4.00 | |||||
| .1614 | 4.10 | |||||
| .1640 | 4.17 | #8 | 32 | 36 | ||
| .1772 | 4.50 | |||||
| .1850 | 4.70 | |||||
| .1875 | 4.76 | |||||
| .1900 | 4.83 | #10 | 24 | 32 | ||
| .1969 | 5.00 | |||||
| .2087 | 5.30 | |||||
| .2160 | 5.49 | #12 | 24 | 28 | 32 | |
| .2165 | 5.50 | |||||
| .2188 | 5.56 | |||||
| .2362 | 6.00 | |||||
| .2500 | 6.35 | 1/4 | 20 | 28 | 32 | |
| .2756 | 7.00 | |||||
| .2812 | 7.14 | |||||
| .3125 | 7.94 | 5/16 | 18 | 24 | 32 | |
| .3125 | 7.94 | 1/16 | 27 | |||
| .3150 | 8.00 | |||||
| .3543 | 9.00 | |||||
| .3750 | 9.53 | 3/8 | 16 | 24 | 32 | |
| .3830 | 9.73 | |||||
| .3937 | 10.00 | |||||
| .4050 | 10.29 | 1/8 | 27 | |||
| .4331 | 11.00 | |||||
| .4375 | 11.11 | 7/16 | 14 | 20 | 28 | |
| .4724 | 12.00 | |||||
| .5000 | 12.70 | 1/2 | 13 | 20 | 28 | |
| .5180 | 13.16 | |||||
| .5400 | 13.72 | 1/4 | 18 | |||
| .5512 | 14.00 | |||||
| .5625 | 14.29 | 9/16 | 12 | 18 | 24 | |
| .6250 | 15.88 | 5/8 | 11 | 18 | 24 | |
| .6299 | 16.00 | |||||
| .6560 | 16.66 | |||||
| .6750 | 17.15 | 3/8 | 18 | |||
| .6875 | 17.46 | 11/16 | 24 | |||
| .7087 | 18.00 | |||||
| .7500 | 19.05 | 3/4 | 10 | 16 | 20 | |
| .7874 | 20.00 | |||||
| .8125 | 20.64 | 13/16 | 20 | |||
| .8250 | 20.96 | |||||
| .8400 | 21.34 | 1/2 | 14 | |||
| .8661 | 22.00 | |||||
| .8750 | 22.23 | 7/8 | 9 | 14 | 20 | |
| .9020 | 22.91 | |||||
| .9375 | 23.81 | 15/16 | 20 | |||
| .9449 | 24.00 | |||||
| 1.0000 | 25.40 | 1 | 8 | 14 | 20 | |
| 1.0236 | 26.00 | |||||
| 1.0410 | 26.44 | |||||
| 1.0500 | 26.67 | 3/4 | 14 | |||
| 1.0625 | 26.99 | 1 1/16 | 18 | |||
| 1.0630 | 27.00 | |||||
| 1.1250 | 28.58 | 1 1/8 | 7 | 12 | 18 | |
| 1.1811 | 30.00 | |||||
| 1.1875 | 30.16 | 1 3/16 | 18 | |||
| 1.1890 | 30.20 | |||||
| 1.2500 | 31.75 | 1 1/4 | 7 | 12 | 18 | |
| 1.2598 | 32.00 | |||||
| 1.2992 | 33.00 | |||||
| 1.3090 | 33.25 | |||||
| 1.3125 | 33.34 | 1 5/16 | 18 | |||
| 1.3150 | 33.40 | 1 | 11 1/2 | |||
| 1.3750 | 34.93 | 1 3/8 | 6 | 12 | 18 | |
| 1.3780 | 35.00 | |||||
| 1.4173 | 36.00 | |||||
| 1.4375 | 36.51 | 1 7/16 | 18 | |||
| 1.4920 | 37.90 | |||||
| 1.4961 | 38.00 | |||||
| 1.5000 | 38.10 | 1 1/2 | 6 | 12 | 18 | |
| 1.5354 | 39.00 | |||||
| 1.5625 | 39.69 | 1 9/16 | 18 | |||
| 1.5748 | 40.00 | |||||
| 1.6250 | 41.28 | 1 5/8 | 18 | |||
| 1.6500 | 41.91 | |||||
| 1.6535 | 42.00 | |||||
| 1.6600 | 42.16 | 1 1/4 | 11 1/2 | |||
| 1.6875 | 42.86 | 1 11/16 | 18 | |||
| 1.7450 | 44.32 | |||||
| UNC-Unified National Course UNF-Unified National FineUNEF-Unified National Extra Fine UNM-Unified National Miniature |
NPT-National Pipe Tapered
*All information is strictly informative