Special Tap Drill Size Chart

TAP TAP DRILL Decimal Drill Size Theo. % of Thread Probable Oversize Probable Hole Size % of Thread
0-80 56 .0465 83 .0015 .0480 74
  3/64 .0469 81 .0015 .0480 71
1-64 54 .0550 89 .0015 .0565 81
  53 .0595 67 .0015 .0610 59
1-72 53 .0595 75 .0015 .0610 67
  1/16 .0625 58 .0015 0640 50
2-56 51 .0670 82 .0017 0687 74
  50 .0770 69 .0017 .0717 62
  49 .0730 56 .0017 .0747 49
2-64 50 .0700 79 .0017 .0717 70
  49 .0730 64 .0017 .0747 56
3-48 48 .0760 85 .0019 .0779 78
  5/64 .0781 77 .0019 .0800 70
  47 .0785 76 .0019 .0804 69
  46 .0810 67 .0019 .0829 60
  45 .0820 63 .0019 .0839 56
3-56 46 .0810 78 .0019 .0829 69
  45 .0820 73 .0019 .0839 65
  44 .0860 56 .0020 .0880 47
4-40 44 .0860 80 .0020 .0880 74
  43 .0890 71 .0020 .0910 65
  42 .0935 57 .0020 .0955 51
  3/32 .0938 56 .0020 .0958 50
4-48 42 .0935 68 .0020 .0955 61
  3/32 .0938 68 .0020 .0958 60
  41 .0960 59 .0020 .0980 52
5-40 40 .0980 83 .0023 .1003 76
  39 .0995 79 .0023 .1018 71
  38 .1015 72 .0023 .1038 65
  37 .1040 65 .0023 .1063 58
5-44 38 .1015 79 .0023 .1038 72
  37 .1040 71 .0023 .1063 63
  36 .1065 63 .0023 .1088 55
6-32 37 .1040 84 .0023 .1063 78
  36 .1065 78 .0023 .1088 72
  7-64 .1094 70 .0026 .1120 64
  35 .1100 69 .0026 .1126 63
  34 .1110 67 .0026 .1136 60
  33 .1130 62 .0026 .1156 55
6-40 34 .1110 83 .0026 .1136 75
  33 .1130 77 .0026 .1156 69
  32 .1160 68 .0026 .1186 60
8-32 29 .1360 69 .0029 .1389 62
  28 .1405 58 .0029 .1434 51
8-36 29 .1360 78 .0029 .1389 70
  28 .1405 68 .0029 .1434 57
  9-64 .1406 68 .0029 .1435 57
10-24 27 .1440 85 .0032 .1472 79
  26 .1470 79 .0032 .1502 74
  25 .1495 75 .0032 .1527 69
  24 .1520 70 .0032 .1552 64
  23 .1540 67 .0032 .1572 61
10-32 5/32 .1563 83 .0032 .1595 75
  22 .1570 81 .0032 .1602 73
  21 .1590 76 .0032 .1622 68
  20 .1610 71 .0032 .1642 64
  19 .1660 59 .0032 .1692 51
12-24 11/64 .1719 82 .0035 .1754 75
  17 .1730 79 .0035 .1765 73
  16 .1770 72 .0035 .1805 66
  15 .1800 67 .0035 .1835 60
  14 .1820 63 .0035 .1855 56
12-28 16 .1770 84 .0035 .1805 77
  15 .1800 78 .0035 .1835 70
  14 .1820 73 .0035 .1855 66
  13 .1850 67 .0035 .1885 59
  3/16 .1875 61 .0036 .1910 54
1/4-20 9 .1960 83 .0038 .1998 77
  8 .1990 79 .0038 .2028 73
  7 .2010 75 .0038 .2048 70
  13/64 .2031 72 .0038 .2069 66
  6 .2040 71 .0038 .2078 65
  5 .2055 69 .0038 .2093 63
  4 .2090 63 .0038 .2128 57
1/4-28 3 .2130 80 .0038 .2168 72
  7/32 .2188 67 .0038 .2226 59
  2 .2210 63 .0038 .2248 55
5/16-18 F .2570 77 .0038 .2608 72
  G .2610 71 .0041 .2651 66
  17/64 .2656 65 .0041 .2697 59
  H .2660 64 .0041 .2701 59
5/16-24 H .2660 86 .0041 .2701 78
  I .2720 75 .0041 .2761 67
  J .2770 66 .0041 .2811 58
3/8-16 5/16 .3125 77 .0044 .3169 72
  O .3160 73 .0044 .3204 68
  P .323 64 .0044 .3274 59
3/8-24 21/64 .3281 87 .0044 .3325 79
  Q .3320 79 .0044 .3364 71
  R .3390 67 .0044 .3434 58
7/16-14 T .3580 86 .0046 .3626 81
  23/64 .3594 84 .0046 .3640 79
  U .3680 75 .0046 .3726 70
  3/8 .3750 67 .0046 .3796 62
  V .3770 65 .0046 .3816 60
7/16-20 W .3860 79 .0046 .3906 72
  25/64 .3906 72 .0046 .3952 65
  X .3970 62 .0046 .4016 55
1/2-13 27/64 .4219 78 .0047 .4266 73
  7/16 .4375 63 .0047 .4422 58
1/2-20 29/64 .4531 72 .0047 .4578 65
9/16-12 15/32 .4688 87 .0048 .4736 82
  31/64 .4844 72 .0048 .4892 68
9/16-18 1/2 .500 87 .0048 .5048 80
  33/64 .5156 65 .0048 .5204 58
5/8-11 17/32 .5313 79 .0049 .5362 75
  35/64 .5469 66 .0049 .5518 62
5/8-18 9/16 .5625 87 .0049 .5674 80
  37/64 .5781 65 .0049 .5831 58
3/4-10 41/64 .6406 84 .0050 .6456 80
  21/32 .6563 72 .0050 .6613 68
3/4-16 11/16 .6875 77 .0050 .6925 71
7/8-9 49/64 .7656 76 .0052 .7708 72
  25/32 .7812 65 .0052 .7864 61
7/8-14 51/64 .7969 84 .0052 .8021 79
  13/16 .8125 67 .0052 .8177 62
1-8 55/64 .8594 87 .0059 .8653 83
  7/8 .875 77 .0059 .8809 73
  57/64 .8906 67 .0059 .8965 64
1-12 29/32 .9063 58 .0059 .9122 54
  29/32 .9063 87 .0059 .9122 81
1-14 59/64 .9219 72 .0060 .9279 67
  15/16 .9375 58 .0060 .9435 52
1-14 59-64 .9219 84 .0060 .9279 78
  15/16 .9375 67 .0060 .9435 61
1-1/8-7 31/32 .9688 84 .0062 .9750 81
  63/64 .9844 76 .0067 .9911 72
  1 1.000 67 .0070 1.007 64
  1-1/64 1.0156 59 .0070 1.0226 55
1-1/8-12 1-1/32 1.0313 87 .0071 1.0384 80
  1-3/64 1.0469 72 .0072 1.0541 66
1-1/4-7 1-3/32 1.0938 84 REAMING RECOMMENDED    
  1-7/64 1.1094 76 REAMING RECOMMENDED    
  1-1/8 1.125 67 REAMING RECOMMENDED    
1-1/4-12 1-5/32 1.1563 87 REAMING RECOMMENDED    
  1-11/64 1.1719 72 REAMING RECOMMENDED    
1-3/8-6 1-3/16 1.1875 87 REAMING RECOMMENDED    
  1-13/64 1.2031 79 REAMING RECOMMENDED    
  1-7/32 1.2188 72 REAMING RECOMMENDED    
  1-15/64 1.2344 65 REAMING RECOMMENDED    
1-3/8-12 1-9/32 1.2813 87 REAMING RECOMMENDED    
  1-19/64 1.2969 72 REAMING RECOMMENDED    
1-1/2-6 1-5/16 1.3125 87 REAMING RECOMMENDED    
  1-21/64 1.3281 79 REAMING RECOMMENDED    
  1-11/32 1.3438 72 REAMING RECOMMENDED    
  1-23/64 1.3594 65 REAMING RECOMMENDED    
1-1/2-12 1-13/32 1.4063 87 REAMING RECOMMENDED    
  1-27/64 1.4219 72 REAMING RECOMMENDED