Metric Size

Decimal
Inch

Fractional
 Inch

1 mm

.039 inch

.0625 inch

1/16”

2 mm

.079 inch

3 mm

.118 inch

.125 inch

1/8”

4 mm

.158 inch

.188 inch

3/16”

5 mm

.197 inch

6 mm

.236 inch

.250 inch

1/4”

6.5 mm

.255 inch

7 mm

.276 inch

.313 inch

5/16”

8 mm

.315 inch

9 mm

.354 inch

.375 inch

3/8”

10 mm

.394 inch

11 mm

.433 inch

.438 inch

7/16”

12 mm

.472 inch

.500 inch

1/2”

13 mm

.512 inch

14 mm

.551 inch

.563 inch

9/16”

15 mm

.591 inch

.625 inch

5/8”

16 mm

.630 inch

17 mm

.669 inch

.688 inch

11/16”

18 mm

.709 inch

19 mm

.748 inch

.750 inch

3/4”

20 mm

.787 inch

.813 inch

13/16”

21 mm

.827 inch

22 mm

.866 inch

.875 inch

7/8”

23 mm

.906 inch

.938 inch

15/16”

24 mm

.945 inch

25 mm

.984 inch

25.4 mm

1.00 inch

1”