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Inch mm fractions

  mm   Inches  fractions  .  fractions  Inches    
          0.10  0.003940    1/254  .    1/64                 0.015625
          0.20  0.007870    1/127  .    1/32                 0.031250
          0.30  0.011810   1/85  .    3/64                 0.046875
          0.40  0.015750   1/63  .    1/16                 0.062500
          0.50  0.019690   1/51  .    5/64                 0.078125
          0.60  0.023620   2/85  .    3/32                 0.093750
          0.70  0.027560   1/36  .    7/64                 0.109375
          0.80  0.031500   1/32  .    1/8                 0.125000
          0.90  0.035430   1/28  .    9/64                 0.140625
          1.00  0.039370   3/76  .    5/32                 0.156250
          2.00  0.078740   3/38  .   11/64                 0.171875
          3.00  0.118110   2/17  .    3/16                 0.187500
          4.00  0.157480   3/19  .   13/64                 0.203125
          5.00  0.196850  12/61  .    7/32                 0.218750
          6.00  0.236220  17/72  .   15/64                 0.234375
          7.00  0.275590   8/29  .    1/4                 0.250000
          8.00  0.314960  23/73  .   17/64                 0.265625
          9.00  0.354330  17/48  .    9/32                 0.281250
        10.00  0.393700  37/94  .   19/64                 0.296875
        11.00  0.433070  13/30  .    5/16                 0.312500
        12.00  0.472440  17/36  .   21/64                 0.328125
        13.00  0.511810  22/43  .   11/32                 0.343750
        14.00  0.551180  43/78  .   23/64                 0.359375
        15.00  0.590550  13/22  .    3/8                 0.375000
        16.00  0.629920  17/27  .   25/64                 0.390625
        17.00  0.669290   2/3  .   13/32                 0.406250
        18.00  0.708660  17/24  .   27/64                 0.421875
        19.00  0.748030   3/4  .    7/16                 0.437500
        20.00  0.787400  37/47  .   29/64                 0.453125
        21.00  0.826770  62/75  .   15/32                 0.468750
        22.00  0.866140  13/15  .   31/64                 0.484375
        23.00  0.905510  67/74  .    1/2                 0.500000
        24.00  0.944880  17/18  .   33/64                 0.515625
        25.00  0.984250  62/63  .   17/32                 0.531250
        26.00  1.023620 1  2/85  .   35/64                 0.546875
        27.00  1.062990 1  1/16  .    9/16                 0.562500
        28.00  1.102360 1  4/39  .   37/64                 0.578125
        29.00  1.141730 1  1/7  .   19/32                 0.593750
        30.00  1.181100 1  2/11  .   39/64                 0.609375
        31.00  1.220470        1.220588 .    5/8                 0.625000
        32.00  1.259840        1.259740 .   41/64                 0.640625
        33.00  1.299210 1  3/10  .   21/32                 0.656250
        34.00  1.338580        1.338710 .   43/64                 0.671875
        35.00  1.377950        1.377778 .   11/16                 0.687500
        36.00  1.417320 1  5/12  .   45/64                 0.703125
        37.00  1.456690        1.456790 .   23/32                 0.718750
        38.00  1.496060 1  1/2  .   47/64                 0.734375
        39.00  1.535430        1.535354 .    3/4                 0.750000
        40.00  1.574800        1.574713 .   49/64                 0.765625
        41.00  1.614170        1.614035 .   25/32                 0.781250
        42.00  1.653540        1.653846 .   51/64                 0.796875
        43.00  1.692910 1  9/13  .   13/16                 0.812500
        44.00  1.732280        1.732394 .   53/64                 0.828125
        45.00  1.771650        1.771739 .   27/32                 0.843750
        46.00  1.811020        1.810811 .   55/64                 0.859375
        47.00  1.850390        1.850000 .    7/8                 0.875000
        48.00  1.889760 1  8/9  .   57/64                 0.890625
        49.00  1.929130        1.928571 .   29/32                 0.906250
        50.00  1.968500        1.968750 .   59/64                 0.921875
        51.00  2.007870 2       .   15/16                 0.937500
        52.00  2.047240 2  1/21  .   61/64                 0.953125
        53.00  2.086610 2  2/23  .   31/32                 0.968750
        54.00  2.125980 2  1/8  .   63/64                 0.984375</t

 

 

 

Inches

 

Abbreviation/Symbol:

  • in

8 inches can be symbolised as either 8in or 8"

.

Unit of Measurement:

  • Length / Distance / Diameter

 

Description:

An inch is a unit of length used in the imperial system, representing 1/12 of a foot and 1/36 of a yard

 

Origin:

The inch has been used as a unit of measurement in the United Kingdom since at least the seventh century, and in 1066 was defined as being equal to the length of three dried barleycorns placed end-to-end.

In the 12th Century, the Scottish inch was defined as being equivalent to the width of an average man's thumb at the base of the nail. Similar units of measurement existed in many areas of what is now modern Europe, with the word for inch in Portuguese, French, Italian, Spanish and numerous other languages being the same or very similar to the word for a thumb.

The English word inch derives from the Latin uncia, meaning one-twelfth part 

Even in the twentieth century, various definitions of the inch were still applied around the world, although these differed by less than 0.001%. In 1930 the British Standards Institution adopted an inch of exactly 25.4mm, with the American Standards Association doing likewise in 1933, and the first country to legally adopt this definition was Canada in 1951.

In 1959 the United States and British Commonwealth countries signed a treaty agreeing to the standardised 25.4mm definition.

 

Worldwide use:

The inch is still a common unit in the USA and is used in Canada and the United Kingdom. In all areas, the metric system of measure is the dominant system.