Tap Drill Charts
INCH_SIZES_-_NATIONAL_COARSE
INCH SIZES - NATIONAL FINE
TAPER PIPE SIZES - NPT
STRAIGHT PIPE SIZES - NPS
METRIC COARSE SIZES
METRIC FINE SIZES

While every precaution has been taken in the preparation of these charts, we assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein.



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Inch Sizes - Coarse

TAP                  DRILL
SIZE                 SIZE

#0-80               3/64
#1-64             #53
#2-56             #50
#3-48             #47
#4-40             #43
#5-40             #38
#6-32             #36
#8-32             #29
#10-24           #25
#12-24           #16
1/4-20            #7
5/16-18            F
3/8-16              5/16
7/16-14            U
1/2-13              27/64
9/16-12            31/64
5/8-11              17/32
3/4-10              21/32
7/8-9                49/64
1"-8                  7/8
1-1/8-7            63/64
1-1/4-7            1-7/64
1-1/2-6            1-21/64
1-3/4-5            1-35/64
2"-4.5              1-25/32
2-1/4-4.5         2-1/32
2-1/2-4            2-1/4
2-3/4-4            2-1/2
3-4                   2-3/4
3-1/4-4            3
3-1/2-4            3-1/4
3-3/4-4            3-1/2
4-4                   3-3/4

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While every precaution has been taken in the preparation of these charts, we assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein.



Inch Sizes - Fine

TAP                 DRILL
SIZE                SIZE

#1-72             #53
#2-64             #50
#3-56             #45
#4-48             #42
#5-44             #37
#6-40             #33
#8-36             #29
#10-32           #21
#12-28           #14
1/4-28            #3
5/16-24            I
3/8-24             Q
7/16-20          25/64
1/2-20             29/64
9/16-18           33/64
5/8-18             37/64
3/4-16             11/16
7/8-14             13/16
1"-14               15/16
1-1/8-12          1-3/64
1-1/4-12          1-11/64
1-1/2-12          1-27/64

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While every precaution has been taken in the preparation of these charts, we assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein.



Metric - Coarse

TAP                       DRILL
SIZE                      SIZE

1mm x .25              .75mm
1.1 x .25                 .85
1.2 x .25                 .95
1.4 x .3                   1.1
1.6 x .35                 1.25
1.7 x .35                 1.3
1.8 x .35                 1.45
2 x .4                      1.6
2.2 x .45                 1.75
2.5 x .45                 2.05
3 x .5                      2.5
3.5 x .6                   2.9
4 x .7                      3.3
4.5 x .75                 3.7
5 x .8                      4.2
6 x 1                       5
7 x 1                       6
8 x 1.25                  6.8
9 x 1.25                  7.8
10 x 1.5                  8.5
11 x 1.5                  9.5
12 x 1.75               10.2
14 x 2                    12
16 x 2                    14
18 x 2.5                 15.5
20 x 2.5                 17.5
22 x 2.5                 19.5
24 x 3                     21
27 x 3                     24
30 x 3.5                  26.5
33 x 3.5                  29.5
36 x 4                     32
39 x 4                     35

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While every precaution has been taken in the preparation of these charts, we assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein.



Metric Fine

TAP                       DRILL
SIZE                      SIZE

4 mm x .35             3.6mm
4 x .5                     3.5
5 x .5                     4.5
6 x .5                     5.5
6 x .75                   5.25
7 x .75                   6.25
8 x .5                     7
8 x .75                   7.25
8 x 1                      7.5
9 x 1                      8
10 x .75                 9.25
10 x 1                    9
10 x 1.25               8.8
11 x 1                   10
12 x .75                11.25
12 x 1                   11
12 x 1.5                10.5
14 x 1                   13
14 x 1.25              12.8
14 x 1.5                12.5
16 x 1                   15
16 x 1.5                14.5
18 x 1                   17
18 x 2                   16
20 x 1                   19
20 x 1.5                18.5
20 x 2                   18
22 x 1                   21
22 x 1.5                20.5
22 x 2                   20
24 x 1.5                22.5
24 x 2                   22
26 x 1.5                24.5
27 x 1.5                25.5
27 x 2                   25
28 x 1.5                26.5
30 x 1.5                28.5
30 x 2                   28
33 x 2                   31
36 x 3                   33
39 x 3                   36

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While every precaution has been taken in the preparation of these charts, we assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein.



Taper Pipe - NPT

TAP                        DRILL
SIZE                       SIZE

1/8-27                     R
1/4-18                     7/16
3/8-18                     37/64
1/2-14                     23/32
3/4-14                     59/64
1"-11.5                   1-5/32
1-1/4-11.5              1-1/2
1-1/2-11.5              1-47/64
2"-11.5                    2-7/32
2-1/2-8                    2-5/8
3"-8                         3-1/4
3-1/2-8                    3-3/4
4"-8                         4-1/4
4-1/2-8                    4-3/4
5-8                           5-9/32
6-8                           6-11/32

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While every precaution has been taken in the preparation of these charts, we assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein.



Straight Pipe - NPS

TAP                        DRILL
SIZE                       SIZE

1/8-27                    S
1/4-18                    29/64
3/8-18                    19/32
1/2-14                    47/64
3/4-14                    15/16
1"-11.5                  1-3/16
1-1/4-11.5             1-33/64
1-1/2-11.5             1-3/4
2"-11.5                   2-7/32
2-1/2-8                   2-21/32
3"-8                        3-9/32
3-1/2-8                   3-25/32
4"-8                        4-9/32
4-1/2-8                   4-25/32
5-8                          5-11/32
6-8                          6-13/32

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While every precaution has been taken in the preparation of these charts, we assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein.





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