So yes you guessed it, I couldn't resist plugging some numbers in to Excel the other day in connection to Filofax organisers, to see if there was something I had over looked or may be explain why some sizes are more popular than others.
So I decided to use the page area of the different sizes to see how they compare to each other between the different sizes.
|Size||H x W (mm)||Area (sq mm)|
|A4||297 x 210||62370|
|A5||210 x 148||31185|
|Personal||171 x 95||16245|
|120 x 81||9720|
|Mini||105 x 67||7035|
Then looking at the page size in terms of percentage of each other and say 'converting' from one size to another size. In the table below, lets say you are using a Personal size and you are going to A5. You start on the top Personal and go down to A5 on the left hand side. This indicates that A5 is 192% in page area relative to Personal size (nearly double the page area)
Another example, this time Personal to Pocket, your page size would be 60% of your current page size.
This got me thinking... if people are tending to cycle between A5 and Personal size. The sort of thing we hear is people like the extra space that A5 gives them, but they don't like the additional bulk of an A5 organiser.
Seeing the figures above it doesn't come as any surprise really as to why the A5 has such an advantage over the Personal size, but people are swapping too much between sizes.
There's almost a case for another size between A5 and Personal, one say that in the same ratio as an A5 page 1:1.4142. This ratio is the same as the square root of 2, or the inverse of Sine 45 degrees, so there is some magic about the ratio of the height versus the width of the European paper sizes.
So I picked a page area roughly between the two sizes about 23000 sq mm, in that ratio you get a page size of 180x127mm or put another way, slightly taller than personal, but about a third wider compared to Personal size or 41% bigger than personal size. This page would look something like this in blue:
So I compromised slightly and made it the same height as Personal (171mm) in the same ratio as A5 that gives a page width of 121 mm and a page area of 20691 sq mm Or 27% bigger than personal size.
This is what it would look like and how it compares to Personal and A5 size. An organiser in this size would need to be wider, but it would be the same height as a Personal size... think of it as Personal +