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Inch/Metric Conversion Table

Inch/metric Coversion Table
Conversion Factors for The U.S. Customary System (USCS) and The International System of Units (SI)

Fraction
Inch
Decimal
mm
0.00004
0.001
0.00039
0.01
0.0010
0.025
0.0020
0.051
0.0030
0.0762
0.00394
0.1
0.0050
0.1270
0.00984
0.25
0.0100
0.254
1/64
0.0156
0.396
1/32
0.0312
0.793
0.03937
1.
3/64
0.0469
1.191
0.0591
1.5
1/16
0.0625
1.5875
5/64
0.0781
1.984
0.0787
2.
3/32
0.0937
2.381
0.0984
2.5
0.1000
2.54
7/64
0.1094
2.778
0.1181
3.
1/8
0.1250
3.175
0.1378
3.5
9/64
0.1406
3.571
5/32
0.1562
3.968
0.1575
4.
11/64
0.1719
4.366
0.1772
4.5
3/16
0.1875
4.7625
0.1969
5.
13/64
0.2031
5.159
7/32
0.2187
5.556
15/64
0.2344
5.953
0.2362
6.
1/4
0.2500
6.35
17/64
0.2656
6.746
0.2756
7.
9/32
0.2812
7.1437
19/64
0.2969
7.5406
5/16
0.3125
7.9375
0.3150
8.
21/64
0.3281
8.334
11/32
0.3437
8.731
0.3543
9.
23/64
0.3594
9.1281
3/8
0.3750
9.525
25/64
0.3906
9.9219
0.3937
10.
13/32
0.4062
10.318
27/64
0.4219
10.716
0.4331
11.
7/16
0.4375
11.1125
29/64
0.4531
11.509
15/32
0.4687
11.906
0.4724
12.
31/64
0.4844
12.303
1/2
0.5000
12.7
0.5118
13.
33/64
0.5156
13.096
17/32
0.5312
13.493
35/64
0.5469
13.891
0.5512
14.
9/16
0.5625
14.2875
37/64
0.5781
14.684
0.5906
15.
19/32
0.5937
15.081
39/64
0.6094
15.478
5/8
0.6250
15.875
0.6299
16.
41/64
0.6406
16.271
21/32
0.6562
16.668
0.6693
17.
43/64
0.6719
17.066
11/16
0.6875
17.4625
45/64
0.7031
17.859
0.7086
18.
23/32
0.7187
18.256
47/64
0.7344
18.653
0.7480
19.
3/4
0.7500
19.05
49/64
0.7656
19.446
25/32
0.7812
19.843
0.7874
20.
51/64
0.7969
20.240
13/16
0.8125
20.6375
0.8268
21.
53/64
0.8281
21.034
27/32
0.8437
21.431
55/64
0.8594
21.828
0.8661
22.
7/8
0.8750
22.225
57/64
0.8906
22.621
0.9055
23.
29/32
0.9062
23.018
59/64
0.9219
23.416
15/16
0.9375
23.8125
0.9449
24.
61/64
0.9531
24.209
31/32
0.9687
24.606
0.9843
25.
63/64
0.9844
25.003
1
1.0000
25.4
1.0630
27.
1.1024
28.
1.1811
30.
1 1/4
1.2500
31.75
1.2992
33.
1.3780
35.
1.4173
36.
1 1/2
1.5000
38.1
1.5354
39.
1.5748
40.
1.6535
42.
1 3/4
1.7500
44.45
1.7717
45.
1.8898
48.
1.9685
50.
2
2.000
50.8
2.0472
52.
2.1654
55.
2.2047
56.
2 1/4
2.2500
57.15
2.3622
60.
2 1/2
2.5000
63.5
2.5197
64.
2 3/4
2.7500
69.85
2.8346
72.
2.9528
75.
3
3.0000
76.2
3.1496
80.
3 1/4
3.2500
82.55
3 1/2
3.5000
88.9
3.5433
90.
3 3/4
3.7500
95.25
3.9370
100.
4
4.0000
101.6
4 1/4
4.2500
107.95
4.3307
110.
4 1/2
4.5000
114.3
4.7244
120.
4 3/4
4.7500
120.65
5
5.0000
127.
5 1/2
5.5000
139.7

 

Conversion Factors for The U.S. Customary System (USCS) and The International System of Units (SI)

USCS to SI SI to USCS
Length 1 in = 25.4 mm 1mm = 0.0393701 in
Surface Texture 1µ in = 0.0254 um 1µm = 39.3701 µ in
Area 1 in2 = 645.16 mm2 1mm2 = 0.00155 in2
Volume 1 in3 = 16.3871 cm3 1cm3 = 0.0610237 in3
Mass 1 lb = 0.45359 kg 1 kg = 2.20462 lb
1 oz = 28.3495 g 1g = 0.035274 oz

Density 1lb/in3 = 27.6799 g/cm3 1 g/cm3 = 0.036 lb/in3
Force 1 lbf = 4.44822 N 1N = 0.224809 lbf
Moment of Force (Torque) 1 lbf in = 0.112985 Nm 1Nm = 8.85 lbf in
Stress 1 lbf/in2 = 0.00689 N/mm2 1 N/mm2 = 145.038 lbf/in2

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