If you consider yourself a handyman of fine woodworking, exquisite metallurgy, and other fixing pursuits, you probably already know the sheer importance of being aware of different drill bit sizes and their immense importance.
Indeed, drill a hole in your drywall that’s too big for the nail or screw you designated for it, and now you have to either seal the hole or somehow make the screw in question thicker. Both of these scenarios have one thing in common – they’re annoying and will make your small project take longer than needed to finish. (
Plus, your drywall has been compromised!)
Now, in this article, we’re going to provide to you a brief guide on how to figure out what drill bit size you need, depending on different gauges you may want to use, and according to different metric systems.
Before we start, though, let’s review a couple of important matters related to drilling bits.
How to Choose Drill Bits
There are several parameters about choosing the right drill bit for the project at hand. For example, when it comes to figuring out the shape of the drill bits you’ll be using, the most important parameter to look into would be the material you’re working with.
In case you want to drill into wood, what you want to look for are drill bits that have a minute pointed tip at the end, while the rest is flat. This type of drill will drive hard into the wood and will be able to carve into it easily, and without overheating the wood too much. If you’re looking for some extra durability, you may want to get a package of titanium-coated drill bits.
Masonry drill bits have a sloped top so that they can drive into the concrete, cinder, or even tile with ease. (
Well, drilling into masonry is never really easy, but it’s certainly much easier doing it with these specialized sloped drill bits.) Many masonry drill bit manufacturers also cover their bits with carbide to make them last longer and to further improve their toughness.
Last but not least, metal drill bits have an angled point with a sharp tip at its end. Usually, you can recognize them because they’re painted black. An interesting thing about these drill bits is that they come in a special series called HSS (
which means ‘high-speed steel’) These will be better than just the regular drill bits, so if you’re looking for speed and durability, look for that HSS label, as well.
Drill Bit Chart for Gauge Letters
As you probably already know, there are several ways to classify drill bit sizes. One of the most commonly used in North America would be the so-called Letter way, which uses the alphabet to mark different sizes. (
The chart starts with A, which is the smallest one, and ends with Z, the largest one.)
| Gauge |
Dec. (in.) |
Dec. (mm) |
|
Gauge |
Dec. (in.) |
Dec. (mm) |
| A |
0.234 |
5.944 |
|
N |
0.302 |
7.671 |
| B |
0.238 |
6.045 |
|
O |
0.316 |
8.026 |
| C |
0.242 |
6.147 |
|
P |
0.323 |
8.204 |
| D |
0.246 |
6.248 |
|
Q |
0.332 |
8.433 |
| E |
0.25 |
6.35 |
|
R |
0.339 |
8.611 |
| F |
0.257 |
6.528 |
|
S |
0.348 |
8.839 |
| G |
0.261 |
6.629 |
|
T |
0.358 |
9.093 |
| H |
0.266 |
6.756 |
|
U |
0.368 |
9.347 |
| I |
0.272 |
6.909 |
|
V |
0.377 |
9.576 |
| J |
0.277 |
7.036 |
|
W |
0.386 |
9.804 |
| K |
0.281 |
7.137 |
|
X |
0.397 |
10.08 |
| L |
0.29 |
7.366 |
|
Y |
0.404 |
10.26 |
| M |
0.295 |
7.493 |
|
Z |
0.413 |
10.49 |
Drill Chart for Gauge 1-96
Another way of representing the drill bit sizes would be to use numbers. The way this works is that 96 represents the smallest bit and then the largest one is at number 1. Here’s the chart for these two and all the sizes in between.
| Gauge |
Dec. (in.) |
Dec. (mm) |
|
Gauge |
Dec. (in.) |
Dec. (mm) |
| 96 |
0.0063 |
0.16 |
|
46 |
0.081 |
2.057 |
| 95 |
0.0067 |
0.17 |
|
45 |
0.082 |
2.083 |
| 94 |
0.0071 |
0.18 |
|
44 |
0.086 |
2.184 |
| 93 |
0.0075 |
0.191 |
|
43 |
0.089 |
2.261 |
| 92 |
0.0079 |
0.201 |
|
42 |
0.0935 |
2.375 |
| 91 |
0.0083 |
0.211 |
|
41 |
0.096 |
2.438 |
| 90 |
0.0087 |
0.221 |
|
40 |
0.098 |
2.489 |
| 89 |
0.0091 |
0.231 |
|
39 |
0.0995 |
2.527 |
| 88 |
0.0095 |
0.241 |
|
38 |
0.1015 |
2.578 |
| 87 |
0.01 |
0.254 |
|
37 |
0.104 |
2.642 |
| 86 |
0.0105 |
0.267 |
|
36 |
0.1065 |
2.705 |
| 85 |
0.011 |
0.279 |
|
35 |
0.11 |
2.794 |
| 84 |
0.0115 |
0.292 |
|
34 |
0.111 |
2.819 |
| 83 |
0.012 |
0.305 |
|
33 |
0.113 |
2.87 |
| 82 |
0.0125 |
0.318 |
|
32 |
0.116 |
2.946 |
| 81 |
0.013 |
0.33 |
|
31 |
0.12 |
3.048 |
| 80 |
0.0135 |
0.343 |
|
30 |
0.1285 |
3.264 |
| 79 |
0.0145 |
0.368 |
|
29 |
0.136 |
3.454 |
| 78 |
0.016 |
0.406 |
|
28 |
0.1405 |
3.569 |
| 77 |
0.018 |
0.457 |
|
27 |
0.144 |
3.658 |
| 76 |
0.02 |
0.508 |
|
26 |
0.147 |
3.734 |
| 75 |
0.021 |
0.533 |
|
25 |
0.1495 |
3.797 |
| 74 |
0.0225 |
0.572 |
|
24 |
0.152 |
3.861 |
| 73 |
0.024 |
0.61 |
|
23 |
0.154 |
3.912 |
| 72 |
0.025 |
0.635 |
|
22 |
0.157 |
3.988 |
| 71 |
0.026 |
0.66 |
|
21 |
0.159 |
4.039 |
| 70 |
0.028 |
0.711 |
|
20 |
0.161 |
4.089 |
| 69 |
0.0292 |
0.742 |
|
19 |
0.166 |
4.216 |
| 68 |
0.031 |
0.787 |
|
18 |
0.1695 |
4.305 |
| 67 |
0.032 |
0.813 |
|
17 |
0.173 |
4.394 |
| 66 |
0.033 |
0.838 |
|
16 |
0.177 |
4.496 |
| 65 |
0.035 |
0.889 |
|
15 |
0.18 |
4.572 |
| 64 |
0.036 |
0.914 |
|
14 |
0.182 |
4.623 |
| 63 |
0.037 |
0.94 |
|
13 |
0.185 |
4.699 |
| 62 |
0.038 |
0.965 |
|
12 |
0.189 |
4.801 |
| 61 |
0.039 |
0.991 |
|
11 |
0.191 |
4.851 |
| 60 |
0.04 |
1.016 |
|
10 |
0.1935 |
4.915 |
| 59 |
0.041 |
1.041 |
|
9 |
0.196 |
4.978 |
| 58 |
0.042 |
1.067 |
|
8 |
0.199 |
5.055 |
| 57 |
0.043 |
1.092 |
|
7 |
0.201 |
5.105 |
| 56 |
0.0465 |
1.181 |
|
6 |
0.204 |
5.182 |
| 55 |
0.052 |
1.321 |
|
5 |
0.2055 |
5.22 |
| 54 |
0.055 |
1.397 |
|
4 |
0.209 |
5.309 |
| 53 |
0.0595 |
1.511 |
|
3 |
0.213 |
5.41 |
| 52 |
0.0635 |
1.613 |
|
2 |
0.221 |
5.613 |
| 51 |
0.067 |
1.702 |
|
1 |
0.228 |
5.791 |
| 50 |
0.07 |
1.778 |
|
|
|
|
| 49 |
0.073 |
1.854 |
|
|
|
|
| 48 |
0.076 |
1.93 |
|
|
|
|
| 47 |
0.0785 |
1.994 |
|
|
|
|
Drill Bit Size Chart – Fractions + Metric + Imperial System
In the chart below, you can see the different values expressed in three common ways. (
Well, depending on where you live.) The first column is dedicated to fractions, while the following two represent the same value expressed in the imperial and metric systems. The smallest value starts at 1/64 and it goes all the way to the largest one at 21/32.
| Diam. |
Dec. (In.) |
Dec. (mm) |
|
Diam. |
Dec. (In.) |
Dec. (mm) |
| 1/64 |
0.0156 |
0.3969 |
|
11/32 |
0.3438 |
8.7313 |
| 1/32 |
0.0313 |
0.7938 |
|
23/64 |
0.3594 |
9.1281 |
| 3/64 |
0.0469 |
1.1906 |
|
3/8 |
0.375 |
9.525 |
| 1/16 |
0.0625 |
1.5875 |
|
25/64 |
0.3906 |
9.9219 |
| 5/64 |
0.0781 |
1.9844 |
|
13/32 |
0.4063 |
10.3188 |
| 3/32 |
0.0938 |
2.3813 |
|
27/64 |
0.4219 |
10.7156 |
| 7/64 |
0.1094 |
2.7781 |
|
7/16 |
0.4375 |
11.1125 |
| 1/8 |
0.125 |
3.175 |
|
29/64 |
0.4531 |
11.5094 |
| 9/64 |
0.1406 |
3.5719 |
|
15/32 |
0.4688 |
11.9063 |
| 5/32 |
0.1563 |
3.9688 |
|
31/64 |
0.4844 |
12.3031 |
| 11/64 |
0.1719 |
4.3656 |
|
1/2 |
0.5 |
12.7 |
| 3/16 |
0.1875 |
4.7625 |
|
33/64 |
0.5156 |
13.0969 |
| 13/64 |
0.2031 |
5.1594 |
|
17/32 |
0.5313 |
13.4938 |
| 7/32 |
0.2188 |
5.5563 |
|
35/64 |
0.5469 |
13.8906 |
| 15/64 |
0.2344 |
5.9531 |
|
9/16 |
0.5625 |
14.2875 |
| 1/4 |
0.25 |
6.35 |
|
37/64 |
0.5781 |
14.6844 |
| 17/64 |
0.2656 |
6.7469 |
|
19/32 |
0.5938 |
15.0813 |
| 9/32 |
0.2813 |
7.1438 |
|
39/64 |
0.6094 |
15.4781 |
| 19/64 |
0.2969 |
7.5406 |
|
5/8 |
0.625 |
15.875 |
| 5/16 |
0.3125 |
7.9375 |
|
41/64 |
0.6406 |
16.2719 |
| 21/64 |
0.3281 |
8.3344 |
|
21/32 |
0.6563 |
16.6688 |
So, these are the drill bit charts most commonly used in North America. Hope this article helped you find the right size of bit drill for the project at hand. Best of luck with your handyman’s projects and keep on rockin’!
