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