A0 is a square meter. Its sides are self similar, such that the ratio of long to short edge stays the same when you cut one in the middle, and thus create a new long and short edge.
Each cut produces two sheets of the next Ax number, so A4 is four times halved compared to A0, or a sixteenth of a square meter.
That property of being able to halve is achieved with a ratio of the square root of 2, so unfortunately the measurements in absolute numbers get pretty odd.
Add in the fact that paper manufacturers round the numbers down, that “perfect” half size goes out the window immediately on the first division. And gets worse as the paper size gets smaller.
A0 is a square meter. Its sides are self similar, such that the ratio of long to short edge stays the same when you cut one in the middle, and thus create a new long and short edge.
Each cut produces two sheets of the next Ax number, so A4 is four times halved compared to A0, or a sixteenth of a square meter.
That property of being able to halve is achieved with a ratio of the square root of 2, so unfortunately the measurements in absolute numbers get pretty odd.
Add in the fact that paper manufacturers round the numbers down, that “perfect” half size goes out the window immediately on the first division. And gets worse as the paper size gets smaller.