Machine Screws

Slotted / Phillips Head
Round Head
Flat Head
Pan Head

Sheet Metal Screws

Type A/AB Point
Flat Head
Pan Head
Hex Washer Head

Self Drilling Screws

TEK Type
Hex Washer Head
Sealing Washers

Drywall & Wood Screws

Bugle Head
Flat Head
Decking

Decimal and Millimeter Equivalents

DecimalsMillimetersDecimalsMillimeters
1/640.0156250.39717/32.5312513.494
1/32.031250.179435/64.54687513.891
3/64.0468751.1919/16.562514.288
1/16.06251.58837/64.57812514.684
5/64.0781251.98419/32.5937515.478
3/32.093752.38139/64.50937515.478
7/64.1093752.7785/8.625015.875
1/8.12503.17541/64.64062516.272
9/64.1406253.57221/32.6562516.669
5/32.156253.96943/64.67187517.066
11/64.1718754.36611/18.687517.463
3/16.18754.76345/64.70312517.859
13/64.2031255.15923/32.7187518.256
7/32.218755.55647/64.7337518.653
15/64.2343755.9533/4.750019.050
1/4.25006.35049/64.76562519.477
17/64.2656256.74725/32.7812519.844
9/32.281257.14451/64.79687520.241
19/64.2968757.54113/16.812520.638
5/16.31257.93853/64.82812521.034
21/64.3281258.33427/34.8437521.431
11/32.343758.73155/64.85937521.828
23/64.3593759.1287/8.875022.225
3/8.37509.52557/64.89062522.622
25/64.3906259.92229/64.9062523.019
13/32.4062510.31959/64.92187523.416
27/64.42187510.71615/16.937523.813
7/16.437511.11361/64.95312524.606
29/64.45312511.50931/32.9687524.606
15/32.4687511.90663/64.98437525.003
31/64.48437512.30311.00025.400
1/2.500012.700One mm = .03937
33/64.51562513.097

Threads Per Inch

SizeCoarse UNCFine UNFBasic Major Diameter
06480.0600
16472.0730
25864.0860
34856.0990
44048.1120
54044.1250
63240.1380
83236.1640
102432.1900
122428.2160
1/42028.2500
5/161824.3750
3/81624.3125
7/161420.4375
1/21320.5000
9/161218.5625
5/81118.6250
3/41016.7500
7/8914.8750
18141.000
1 1/87121.125
1 1/47121.250
1 3/86121.500
1 1/26121.500
1 5/85 1/2-1.625
1 3/45121.750
1 7/85-1.875
24 1/2122.00
2 1/44 1/2-2.250
2 1/24-2.500
2 3/44-2.750
34-3.000
3 1/44-3.250
3 1/24-3.500
3 3/44-3.750
44-4.000