GM Service Manual Online
For 1990-2009 cars only

Refer to the following table for equivalent of fractions to decimals in English (inches), to metric (millimeters).

Fraction (in)

Decimal (in)

Metric (mm)

1/64

0.015625

0.39688

1/32

0.03125

0.79375

3/64

0.046875

1.19062

1/16

0.0625

1.5875

5/64

0.078125

1.98437

3/32

0.09375

2.38125

7/64

0.109375

2.77812

1/8

0.125

3.175

9/64

0.140625

3.57187

5/32

0.15625

3.96875

11/64

0.171875

4.36562

3/16

0.1875

4.7625

13/64

0.203125

5.15937

7/32

0.21875

5.55625

15/64

0.234375

5.95312

1/4

0.25

6.35

17/64

0.265625

6.74687

9/32

0.28125

7.14375

19/64

0.296875

7.54062

5/16

0.3125

7.9375

21/64

0.328125

8.33437

11/32

0.34375

8.73125

23/64

0.359375

9.12812

3/8

0.375

9.525

25/64

0.390625

9.92187

13/32

0.40625

10.31875

27/64

0.421875

10.71562

7/16

0.4375

11.1125

29/64

0.453125

11.50937

15/32

0.46875

11.90625

31/64

0.484375

12.30312

1/2

0.5

12.7

33/64

0.515625

13.09687

17/32

0.53125

13.49375

35/64

0.546875

13.89062

9/16

0.5625

14.2875

37/64

0.578125

14.68437

19/32

0.59375

15.08125

39/64

0.609375

15.47812

5/8

0.625

15.875

41/64

0.640625

16.27187

21/32

0.65625

16.66875

43/64

0.671875

17.06562

11/16

0.6875

17.4625

45/64

0.703125

17.85937

23/32

0.71875

18.25625

47/64

0.734375

18.65312

3/4

0.75

19.05

49/64

0.765625

19.44687

25/32

0.78125

19.84375

51/64

0.796875

20.24062

13/16

0.8125

20.6375

53/64

0.828125

21.03437

27/32

0.84375

21.43125

55/64

0.859375

21.82812

7/8

0.875

22.225

57/64

0.890625

22.62187

29/32

0.90625

23.01875

59/64

0.921875

23.41562

15/16

0.9375

23.8125

61/64

0.953125

24.20937

31/32

0.96875

24.60625

63/64

0.984375

25.00312

1

1.0

25.4