Drill & Tap Sizes by Thread & Screw

Machine Screw
Size

Threads
Per Inch

Tap Drills

Clearance Holes by Drills

Alum, Brass,
& Plasitcs

75% Thread

Stainless Steel,
Steels & Iron

50% Thread

Most Material Types

Close Fit

Free Fit

# or Dia

Drill Size
Number or Letter

Decimal
Equiv.

Drill Size
Number or Letter

Decimal
Equiv.

Drill Size
Number or Letter

Decimal
Equiv.

Drill Size
Number or Letter

Decimal
Equiv.

0

80

3/64

.0469

55

.0520

52

.0635

50

.0700

1

64

53

.0595

1/16

.0625

48

.0760

46

.0810

72

53

.0595

52

.0635

2

56

50

.0700

49

.0730

43

.0890

41

.0960

64

50

.0700

48

.0760

3

48

47

.0785

44

.0860

37

.1040

35

.1100

56

45

.0820

43

.0890

4

40

43

.0890

41

.0960

32

.1160

30

.1285

48

42

.0935

40

.0980

5

40

38

.1015

7/64

.1094

30

.1285

29

.1360

44

37

.1040

35

.1100

6

32

36

.1065

32

.1160

27

.1440

25

.1495

40

33

.1130

31

.1200

8

32

29

.1360

27

.1440

18

.1695

16

.1770

36

29

.1360

26

.1470

10

24

25

.1495

20

.1610

9

.1960

7

.2010

32

21

.1590

18

.1695

12

24

16

.1770

12

.1890

2

.2210

1

.2280

28

14

.1820

10

.1935

32

13

.1850

9

.1960

1/4

20

7

.2010

7/32

.2188

F

.2570

H

.2660

28

3

.2130

1

.2280

32

7/32

.2188

1

.2280

5/16

18

F

.2570

J

.2770

P

.3230

Q

.3320

24

I

.2720

9/32

.2812

32

9/32

.2812

L

.2900

3/8

16

5/16

.3125

Q

.3320

W

.3860

X

.3970

24

Q

.3320

S

.3480

32

11/32

.3438

T

.3580

7/16

14

U

.3680

25/64

.3906

29/64

.4531

15/32

.4687

20

25/64

.3906

13/32

.4062

28

Y

.4040

Z

.4130

1/2

13

27/64

.4219

29/64

.4531

33/64

.5156

17/32

.5312

20

29/64

.4531

15/32

.4688

28

15/32

.4688

15/32

.4688

9/16

12

31/64

.4844

33/64

.5156

37/64

.5781

19/32

.5938

18

33/64

.5156

17/32

.5312

24

33/64

.5156

17/32

.5312

5/8

11

17/32

.5312

9/16

.5625

41/64

.6406

21/32

.6562

18

37/64

.5781

19/32

.5938

24

37/64

.5781

19/32

.5938

11/16

24

41/64

.6406

21/32

.6562

45/64

.7031

23/32

.6562

3/4

10

21/32

.6562

11/16

.6875

49/64

.7656

25/32

.7812

16

11/16

.6875

45/64

.7031

20

45/64

.7031

23/32

.7188

13/16

20

49/64

.7656

25/32

.7812

53/64

.8281

27/32

.8438

7/8

9

49/64

.7656

51/64

.7969

57/64

.8906

29/32

.9062

14

13/16

.8125

53/64

.8281

20

53/64

.8281

27/32

.8438

15/16

20

57/64

.8906

29/32

.9062

61/64

.9531

31/32

.9688

1

8

7/8

.8750

59/64

.9219

1-1/64

1.0156

1-1/32

1.0313

12

15/16

.9375

61/64

.9531

20

61/64

.9531

31/32

.9688