Screw Sizes with US (Inch) and Metric
Our screws are supplied worldwide. We often see different customers' size charts, including metric, imperial, and American. It's important to understand these dimensions and know what a good deal they are. These dimensions are easily known using our most accurate digital calipers (decimal inches to screw size). But what about when you don’t have calipers?
Take a look at the screw sizes below.
US fractions converted to metric millimeters for more common screw sizes
US Screw size conversion chart:
|
Screw Size |
Inch Decimal |
Nearest Fraction |
Metric Equivalent |
|
#0 |
0.060 in. |
1/16" |
1.52 mm |
|
#1 |
0.073 in. |
5/64" |
1.85 mm |
|
#2 |
0.086 in. |
3/32" |
2.18 mm |
|
#3 |
0.099 in. |
7/64" |
2.51 mm |
|
#4 |
0.112 in. |
7/64" |
2.84 mm |
|
#5 |
0.125 in. |
1/8" |
3.18 mm |
|
#6 |
0.138 in. |
9/64" |
3.51 mm |
|
#8 |
0.164 in. |
5/32" |
4.17 mm |
|
#10 |
0.190 in. |
3/16" |
4.83 mm |
|
#12 |
0.216 in. |
7/32" |
5.49 mm |
|
#14 |
0.250 in. |
1/4" |
6.35 mm
|
US Fraction to Metric mm equivalent chart:
US |
METRIC |
CONT. US |
CONT. METRIC |
|
|
1/16" |
1.59 mm |
1-3/8" |
34.93 mm |
|
|
1/8" |
3.18 mm |
1-1/2" |
38.10 mm |
|
|
3/16" |
4.76 mm |
1-5/8" |
41.28 mm |
|
|
1/4" |
6.35 mm |
1-3/4" |
44.45 mm |
|
|
5/16" |
7.94 mm |
1-7/8" |
47.63 mm |
|
|
3/8" |
9.53 mm |
2" |
50.80 mm |
|
|
7/16" |
11.11 mm |
2-1/4" |
57.15 mm |
|
|
1/2" |
12.70 mm |
2-1/2" |
63.50 mm |
|
|
9/16" |
14.29 mm |
2-3/4" |
69.85 mm |
|
|
5/8" |
15.88 mm |
3" |
76.20 mm |
|
|
11/16" |
17.46 mm |
3-1/4" |
82.55 mm |
|
|
3/4" |
19.05 mm |
3-1/2" |
88.90 mm |
|
|
7/8" |
22.23 mm |
3-3/4" |
95.25 mm |
|
|
1" |
25.40 mm |
4" |
101.6 mm |
|
|
1-1/4" |
31.75 mm |
