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What Are The Dimensions Of A4, A3 And A2 Paper In Centimetres And Who Decided On Their Size?

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    A4 paper size, widely used in the United Kingdom and Europe, is measured as 210 mm by 297 mm. This is the size typically used for letters and other correspondence.
    A3 paper is larger (yes, as the numbers get smaller, the sheets of paper get bigger), measuring 297 by 420 mm. And A2 paper is larger yet, measuring 420 x 594 mm, which few personal printers can handle.
    You may notice that one edge of each paper is double the next smaller size. For instance, A4 measures 210 by 297mm, while A3 measures 420 mm on the long edge. 420 is double 210. That’s because each smaller sheet is calculated on half the dimensions of the larger.
    For instance, fold an A3 sheet in half on the long edge (420 mm), and you’ll have a sheet of A4, measuring 210 mm by 297 mm. A0 paper, the paper from which all these other sizes are created, measures 841 mm by 1189 mm, which measures one square meter.
    5 0

    Jmack13 

    answered 1 year ago

    Is it 210 x 297 cm or mm? I work in a law office in Canada, and have to print something out on A4, which means I have to use a ruler to cut the paper in the proper dimensions. (I know, we're the strange ones)
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    Kim264

    Kim264

    commented 1 year ago

    It's definitely 210mm x 297mm (or 21.0cm x 29.7cm).
    If it were really as expressed by jmack it would mean the long side would be nearly 3 metres long (quite a task to tackle with your ruler and scissors! ;-) ).
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    Cecilia23

    Cecilia23

    commented 9 months ago

    It's definitely that number in millimetres; if it were in the centimetres expressed by jmack it would mean the long side would be nearly 3 metres long!

    Quite a task to tackle with ruler and scissors! ;-) ).
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    Cecilia23

    Cecilia23

    commented 9 months ago

    + 2 Comments

      These paper sizes are defined by Standard 216 from the International Standards Office (ISO 216)
      This standard allowed paper sizes to be standardized across the world (although most countries have their own variants).
      The paper size is based on a sheet with an area of 1 square metre with a height to width ratio of 1.414 (= square root of 2). This is called A0
      If you chop this sheet in half so that the longer edge is halved you get two sheets of A1. Chop an A1 sheet in half and you get two sheets of A2. etc.etc.
      In reality it is usual for the measurements to be rounded to the nearest millimetre to keep the numbers neat and the ISO216 standard has a built in tolerance of between +/-1.5mm to +/-3mm depending on sheet size.
      These are generally accepted dimensions for the sizes: A0 841 × 1189, A1 594 × 841, A2 420 × 594, A3 297 × 420, A4 210 × 297, A5 148 × 210, A6 105 × 148, A7 74 × 105

      I don't know why the square root of 2 was chosen as the ratio… If anyone knows, please tell!
      1 0

      Widjet 

      answered 3 years ago

      I don't know the answer for sure, but (as an ignoramus in maths) I think I have worked it out. It goes back to Pythagoras. A: If one side of a right angle triangle is root 1 (= 1) and the adjacent is root 2, the hypotenuse will be root 3. B: Another aspect: the ratio 1:root2 = root2:2 Thus this proportion will enable you to double the short side each time so you can fold AO neatly into half and get A1, A1 into A2, A2 into A3 etc.
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      Guest

      Guest

      commented 2 years ago

        You you person who has no life
        0 0
        Guest

        Guest 

        answered 5 months ago

        Use this link. It's detailed and the diagrams showing the relationships between sizes make you never forget
        david
        singapore
        0 0
        Guest

        Guest 

        answered 5 months ago

        A4 dimensions
        0 0

        Phalafala 

        answered 3 months ago

          A4 dimension
          0 0
          Guest

          Guest 

          answered 3 months ago

          Guest

          Guest 

          answered 3 months ago

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