different drill bits with varying threats and thicknesses

Drill Bit Size Guide: What Size Do You Need for a #10 Screw?

For any project involving a drill (and, therefore, drill bits), selecting the bit size that matches the screw size is always crucial. If you choose the wrong size, the pilot hole you’re working with won’t match the screw.

If the pilot hole is too big, the screw won’t stay in; if it’s too small, the screw won’t fit, and you may even inadvertently strip the material. Neither situation is a good one. Of course, choosing the right size makes your job easy and enables it to flow well from step to step.

The critical information you need to know for this article is that you need 7/64-inch and 1/8-inch drill bits for softwood and hardwood, respectively.

graphic of different drill bits on white background

Factors to Consider When Selecting the Right Drill Bit Size

You need to consider several factors when selecting the right drill bit size for your project. These include:

  • Type of material being drilled: Wood is the most common for household jobs, but you also have metal, tile, porcelain, concrete, and plastic.
  • Length of the screw
  • Pilot hole size requirements: The hole size should be the same as or shorter than the screw’s center core diameter.
  • Screw diameter and thread count

Practical Tips for Selecting the Right Drill Bit Size

Now that you know the factors you need to consider to select the correct drill bit size, it’s time to review what you need to do when selecting your bits.

  • First, test-fit the screw.
  • Measure the screw thread count and diameter.
  • Align the size of the drill bit with the type of material. Hardwood may need a slightly smaller bit size.

Here are some guidelines for drill bit types and the materials they align with:

  • For metal, you want HSS twist bits.
  • For masonry projects, you want twist bits with a carbide fin.
  • You want a simple twist drill bit for wood, sometimes with a brad point.

woman drilling into wood with drill bit in workshop

Drill Bit Size Charts

For your reference, we’ve included the following exhaustive drill bit size chart. Visit Ecenrode Welds today for all of your drilling needs!

Drill size

Diameter (in)

Diameter (mm)

#107

0.0019

0.0483

0.05 mm

0.0020

0.0500

#106

0.0023

0.0584

#105

0.0027

0.0686

#104

0.0031

0.0787

#103

0.0035

0.0889

#102

0.0039

0.0991

0.1 mm

0.0039

0.1000

#101

0.0043

0.1092

#100

0.0047

0.1194

#99

0.0051

0.1295

#98

0.0055

0.1397

#97

0.0059

0.1499

#96

0.0063

0.1600

#95

0.0067

0.1702

#94

0.0071

0.1803

#93

0.0075

0.1905

0.2 mm

0.0079

0.2000

#92

0.0079

0.2007

#91

0.0083

0.2108

#90

0.0087

0.2210

#89

0.0091

0.2311

#88

0.0095

0.2413

#87

0.0100

0.2540

#86

0.0105

0.2667

#85

0.0110

0.2794

#84

0.0115

0.2921

0.3 mm

0.0118

0.3000

#83

0.0120

0.3048

#82

0.0125

0.3175

#81

0.0130

0.3302

#80

0.0135

0.3429

#79

0.0145

0.3680

1/64 in

0.0156

0.3969

0.4 mm

0.0158

0.4000

#78

0.0160

0.4064

#77

0.0180

0.4572

0.5 mm

0.0197

0.5000

#76

0.0200

0.5080

#75

0.0210

0.5334

#74

0.0225

0.5715

0.6 mm

0.0236

0.6000

#73

0.0240

0.6096

#72

0.0250

0.6350

#71

0.0260

0.6604

0.7 mm

0.0276

0.7000

#70

0.0280

0.7112

#69

0.0292

0.7417

#68

0.0310

0.7874

1/32 in

0.0313

0.7938

0.8 mm

0.0315

0.8000

#67

0.0320

0.8128

#66

0.0330

0.8382

#65

0.0350

0.8890

0.9 mm

0.0354

0.9000

#64

0.0360

0.9144

#63

0.0370

0.9398

#62

0.0380

0.9652

#61

0.0390

0.9906

1 mm

0.0394

1.0000

#60

0.0400

1.0160

#59

0.0410

1.0414

#58

0.0420

1.0668

#57

0.0430

1.0922

1.1 mm

0.0433

1.1000

#56

0.0465

1.1811

3/64 in

0.0469

1.1906

1.2 mm

0.0472

1.2000

1.3 mm

0.0512

1.3000

#55

0.0520

1.3208

#54

0.0550

1.3970

1.4 mm

0.0551

1.4000

1.5 mm

0.0591

1.5000

#53

0.0595

1.5113

1/16 in

0.0625

1.5875

1.6 mm

0.0630

1.6000

#52

0.0635

1.6129

1.7 mm

0.0669

1.7000

#51

0.0670

1.7018

#50

0.0700

1.7780

1.8 mm

0.0709

1.8000

#49

0.0730

1.8542

1.9 mm

0.0748

1.9000

#48

0.0760

1.9304

5/64 in

0.0781

1.9844

#47

0.0785

1.9939

2 mm

0.0787

2.0000

#46

0.0810

2.0574

#45

0.0820

2.0828

2.1 mm

0.0827

2.1000

#44

0.0860

2.1844

2.2 mm

0.0866

2.2000

#43

0.0890

2.2606

2.3 mm

0.0906

2.3000

#42

0.0935

2.3749

3/32 in

0.0938

2.3813

2.4 mm

0.0945

2.4000

#41

0.0960

2.4384

#40

0.0980

2.4892

2.5 mm

0.0984

2.5000

#39

0.0995

2.5273

#38

0.1015

2.5781

2.6 mm

0.1024

2.6000

#37

0.1040

2.6416

2.7 mm

0.1063

2.7000

#36

0.1065

2.7051

7/64 in

0.1094

2.7781

#35

0.1100

2.7940

2.8 mm

0.1102

2.8000

#34

0.1110

2.8194

#33

0.1130

2.8702

2.9 mm

0.1142

2.9000

#32

0.1160

2.9464

3 mm

0.1181

3.0000

#31

0.1200

3.0480

3.1 mm

0.1221

3.1000

1/8 in

0.1250

3.1750

3.2 mm

0.1260

3.2000

#30

0.1285

3.2639

3.3 mm

0.1299

3.3000

3.4 mm

0.1339

3.4000

#29

0.1360

3.4544

3.5 mm

0.1378

3.5000

#28

0.1405

3.5687

9/64 in

0.1406

3.5719

3.6 mm

0.1417

3.6000

#27

0.1440

3.6576

3.7 mm

0.1457

3.7000

#26

0.1470

3.7338

#25

0.1495

3.7973

3.8 mm

0.1496

3.8000

#24

0.1520

3.8608

3.9 mm

0.1535

3.9000

#23

0.1540

3.9116

5/32 in

0.1563

3.9688

#22

0.1570

3.9878

4 mm

0.1575

4.0000

#21

0.1590

4.0386

#20

0.1610

4.0894

4.1 mm

0.1614

4.1000

4.2 mm

0.1654

4.2000

#19

0.1660

4.2164

4.3 mm

0.1693

4.3000

#18

0.1695

4.3053

11/64 in

0.1719

4.3656

#17

0.1730

4.3942

4.4 mm

0.1732

4.4000

#16

0.1770

4.4958

4.5 mm

0.1772

4.5000

#15

0.1800

4.5720

4.6 mm

0.1811

4.6000

#14

0.1820

4.6228

#13

0.1850

4.6990

4.7 mm

0.1850

4.7000

3/16 in

0.1875

4.7625

4.8 mm

0.1890

4.8000

#12

0.1890

4.8006

#11

0.1910

4.8514

4.9 mm

0.1929

4.9000

#10

0.1935

4.9149

#9

0.1960

4.9784

5 mm

0.1969

5.0000

#8

0.1990

5.0546

5.1 mm

0.2008

5.1000

#7

0.2010

5.1054

13/64 in

0.2031

5.1594

#6

0.2040

5.1816

5.2 mm

0.2047

5.2000

#5

0.2055

5.2197

5.3 mm

0.2087

5.3000

#4

0.2090

5.3086

5.4 mm

0.2126

5.4000

#3

0.2130

5.4102

5.5 mm

0.2165

5.5000

7/32 in

0.2188

5.5563

5.6 mm

0.2205

5.6000

#2

0.2210

5.6134

5.7 mm

0.2244

5.7000

#1

0.2280

5.7912

5.8 mm

0.2284

5.8000

5.9 mm

0.2323

5.9000

A

0.2340

5.9436

15/64 in

0.2344

5.9531

6 mm

0.2362

6.0000

B

0.2380

6.0452

6.1 mm

0.2402

6.1000

C

0.2420

6.1468

6.2 mm

0.2441

6.2000

D

0.2460

6.2484

6.3 mm

0.2480

6.3000

1/4 in

0.2500

6.3500

E

0.2500

6.3500

6.4 mm

0.2520

6.4000

6.5 mm

0.2559

6.5000

F

0.2570

6.5278

6.6 mm

0.2598

6.6000

G

0.2610

6.6294

6.7 mm

0.2638

6.7000

17/64 in

0.2656

6.7469

H

0.2660

6.7564

6.8 mm

0.2677

6.8000

6.9 mm

0.2717

6.9000

I

0.2720

6.9088

7 mm

0.2756

7.0000

J

0.2770

7.0358

7.1 mm

0.2795

7.1000

K

0.2810

7.1374

9/32 in

0.2813

7.1438

7.2 mm

0.2835

7.2000

7.3 mm

0.2874

7.3000

L

0.2900

7.3660

7.4 mm

0.2913

7.4000

M

0.2950

7.4930

7.5 mm

0.2953

7.5000

19/64 in

0.2969

7.5406

7.6 mm

0.2992

7.6000

N

0.3020

7.6708

7.7 mm

0.3032

7.7000

7.8 mm

0.3071

7.8000

7.9 mm

0.3110

7.9000

5/16 in

0.3125

7.9375

8 mm

0.3150

8.0000

O

0.3160

8.0264

8.1 mm

0.3189

8.1000

8.2 mm

0.3228

8.2000

P

0.3230

8.2042

8.3 mm

0.3268

8.3000

21/64 in

0.3281

8.3344

8.4 mm

0.3307

8.4000

Q

0.3320

8.4328

8.5 mm

0.3347

8.5000

8.6 mm

0.3386

8.6000

R

0.3390

8.6106

8.7 mm

0.3425

8.7000

11/32 in

0.3438

8.7313

8.8 mm

0.3465

8.8000

S

0.3480

8.8392

8.9 mm

0.3504

8.9000

9 mm

0.3543

9.0000

T

0.3580

9.0932

9.1 mm

0.3583

9.1000

23/64 in

0.3594

9.1281

9.2 mm

0.3622

9.2000

9.3 mm

0.3661

9.3000

U

0.3680

9.3472

9.4 mm

0.3701

9.4000

9.5 mm

0.3740

9.5000

3/8 in

0.3750

9.5250

V

0.3770

9.5758

9.6 mm

0.3780

9.6000

9.7 mm

0.3819

9.7000

9.8 mm

0.3858

9.8000

W

0.3860

9.8044

9.9 mm

0.3898

9.9000

25/64 in

0.3906

9.9219

10 mm

0.3937

10.0000

X

0.3970

10.0838

Y

0.4040

10.2616

13/32 in

0.4063

10.3188

Z

0.4130

10.4902

10.5 mm

0.4134

10.5000

27/64 in

0.4219

10.7156

11 mm

0.4331

11.0000

7/16 in

0.4375

11.1125

11.5 mm

0.4528

11.5000

29/64 in

0.4531

11.5094

15/32 in

0.4688

11.9063

12 mm

0.4724

12.0000

31/64 in

0.4844

12.3031

12.5 mm

0.4921

12.5000

1/2 in

0.5000

12.7000

13 mm

0.5118

13.0000

33/64 in

0.5156

13.0969

17/32 in

0.5313

13.4938

13.5 mm

0.5315

13.5000

35/64 in

0.5469

13.8906

14 mm

0.5512

14.0000

9/16 in

0.5625

14.2875

14.5 mm

0.5709

14.5000

37/64 in

0.5781

14.6844

15 mm

0.5906

15.0000

19/32 in

0.5938

15.0813

39/64 in

0.6094

15.4781

15.5 mm

0.6102

15.5000

5/8 in

0.6250

15.8750

16 mm

0.6299

16.0000

41/64 in

0.6406

16.2719

16.5 mm

0.6496

16.5000

17 mm

0.6693

17.0000

43/64 in

0.6719

17.0656

11/16 in

0.6875

17.4625

17.5 mm

0.6890

17.5000

45/64 in

0.7031

17.8594

18 mm

0.7087

18.0000

23/32 in

0.7188

18.2563

18.5 mm

0.7284

18.5000

47/64 in

0.7344

18.6531

19 mm

0.7480

19.0000

3/4 in

0.7500

19.0500

49/64 in

0.7656

19.4469

19.5 mm

0.7677

19.5000

25/32 in

0.7813

19.8438

20 mm

0.7874

20.0000

51/64 in

0.7969

20.2406

20.5 mm

0.8071

20.5000

13/16 in

0.8125

20.6375

21 mm

0.8268

21.0000

53/64 in

0.8281

21.0344

27/32 in

0.8438

21.4313

21.5 mm

0.8465

21.5000

55/64 in

0.8594

21.8281

22 mm

0.8661

22.0000

7/8 in

0.8750

22.2250

22.5 mm

0.8858

22.5000

57/64 in

0.8906

22.6219

23 mm

0.9055

23.0000

29/32 in

0.9063

23.0188

21/23 in

0.9130

23.1913

59/64 in

0.9219

23.4156

23.5 mm

0.9252

23.5000

15/16 in

0.9375

23.8125

24 mm

0.9449

24.0000

61/64 in

0.9531

24.2094

24.5 mm

0.9646

24.5000

31/32 in

0.9688

24.6063

25 mm

0.9843

25.0000

63/64 in

0.9844

25.0031

1 in

1.0000

25.4000

25.5 mm

1.0039

25.5000

1 1/64 in

1.0156

25.7969

26 mm

1.0236

26.0000

1 1/32 in

1.0313

26.1938

26.5 mm

1.0433

26.5000

1 3/64 in

1.0469

26.5906

1 1/16 in

1.0625

26.9875

27 mm

1.0630

27.0000

1 5/64 in

1.0781

27.3844

27.5 mm

1.0827

27.5000

1 3/32 in

1.0938

27.7813

28 mm

1.1024

28.0000

1 7/64 in

1.1094

28.1781

28.5 mm

1.1221

28.5000

1 1/8 in

1.1250

28.5750

1 9/64 in

1.1406

28.9719

29 mm

1.1417

29.0000

1 5/32 in

1.1563

29.3688

29.5 mm

1.1614

29.5000

1 11/64 in

1.1719

29.7656

30 mm

1.1811

30.0000

1 3/16 in

1.1875

30.1625

30.5 mm

1.2008

30.5000

1 13/64 in

1.2031

30.5594

1 7/32 in

1.2188

30.9563

31 mm

1.2205

31.0000

1 15/64 in

1.2344

31.3531

31.5 mm

1.2402

31.5000

1 1/4 in

1.2500

31.7500

32 mm

1.2598

32.0000

1 17/64 in

1.2656

32.1469

32.5 mm

1.2795

32.5000

1 9/32 in

1.2813

32.5438

1 19/64 in

1.2969

32.9406

33 mm

1.2992

33.0000

1 5/16 in

1.3125

33.3375

33.5 mm

1.3189

33.5000

1 21/64 in

1.3281

33.7344

34 mm

1.3386

34.0000

1 11/32 in

1.3438

34.1313

34.5 mm

1.3583

34.5000

1 23/64 in

1.3594

34.5281

1 3/8 in

1.3750

34.9250

35 mm

1.3780

35.0000

1 25/64 in

1.3906

35.3219

35.5 mm

1.3976

35.5000

1 13/32 in

1.4063

35.7188

36 mm

1.4173

36.0000

1 27/64 in

1.4219

36.1156

36.5 mm

1.4370

36.5000

1 7/16 in

1.4375

36.5125

1 29/64 in

1.4531

36.9094

37 mm

1.4567

37.0000

1 15/32 in

1.4688

37.3063

37.5 mm

1.4764

37.5000

1 31/64 in

1.4844

37.7031

38 mm

1.4961

38.0000

1 1/2 in

1.5000

38.1000

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