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Metric Converter

For all of you old buggers, here you can do conversions from imperial to metric to (inches to mm)
Imperial to Metric Conversion Formula
Example
Imperial Fraction 3/16 is 4.68mm Metric
Conversion Formula is
25mm divided by 16 x 3 equals 4.68mm
And if a measurement has full inches before the Imperial Fraction you must add 25.54mm for each inch  1 Inch is 25.54mm
Example
2 and 3/16 inches converts as below:
2 inches which is 51.08mm and 3/16 inches which is 4.68mm
Conversion into Metric is 55.76mm
Or use the tables below
Fractional and Decimal Inch and Metric Conversion Tables  

Fractional Inches to Decimal Inches to Approximate Millimeters to Practical Millimeters Decimal inches multiplied by 25.4 = approximate mm. N.B. When specifying metric sheet or trim sizes, fractional approximate mm measurements must be rounded off to the nearest whole number; i.e., 50.8 mm is not a practical measurement; it should be rounded up to 51 mm, and 0.5 mm is always rounded down. 

Fractional Inch  Decimal Inch 
Approximate Millimeters  Practical Millimeters  
1/16  0.0625  1.5875  2  
1/8  0.1250  3.1750  3  
3/16  0.1875  4.7625  5  
1/4  0.2500  6.3500  6  
5/16  0.3125  7.9375  8  
3/8  0.3750  9.5250  10  
7/16  0.4375  11.1125  11  
1/2  0.5000  12.7000  13  
9/16  0.5625  14.2875  14  
5/8  0.6250  15.8750  16  
11/16  0.6875  17.4625  17  
3/4  0.7500  19.0500  19  
13/16  0.8125  20.6375  21  
7/8  0.8750  22.2250  22  
15/16  0.9375  23.8125  24  
1.0  25.4  25 
Millimeters to Decimal Inches to Approximate Fractional Inches to Practical Fractional Inches "<" = less than; ">" = greater than 


Millimeters  Decimal Inch  Approximate Fractional Inch  Practical Fractional Inch  
1  0.03937  <3/64  0  
2  0.07874  >5/64  1/16  
3  0.11811  >7/64  1/8  
4  0.15748  >5/32  3/16  
5  0.19685  <13/64  3/16  
6  0.23622  >15/64  1/4  
7  0.27559  <9/32  1/4  
8  0.31496  >5/16  5/16  
9  0.35433  >11/32  3/8  
10  0.39370  <13/32  3/8  
11  0.43307  >27/64  7/16  
12  0.47244  >15/32  1/2  
13  0.51181  <33/64  1/2  
14  0.55118  >35/64  9/16  
15  0.59055  <19/32  9/16  
16  0.62992  <41/64  5/8  
17  0.66929  >21/32  11/16  
18  0.70866  <23/32  11/16  
19  0.74803  >47/64  3/4  
20  0.78740  >25/32  13/16  
21  0.82677  <53/64  13/16  
22  0.86614  >55/64  7/8  
23  0.90551  <29/32  7/8  
24  0.94488  <61/64  15/16  
25  0.98425  >31/32  1 