‘A’ what??? And what’s a ‘C’???
We are often asked what size is A4? Easy 210x297mm but how does it work? Well the higher the number the smaller the size. The size is changed by halving the long edge. So A5 which is the most popular size for leaflets is half the long dimension of A4 so: A4=210x297mm and A5=210x148mm so what do you think A6 is? Yes you got it… A6=148x105mm. A6 by the way is the size of a Post card and many pads are A6.
So what is a ‘C’ size i.e. C4? The ‘C’ sizes are designed for envelopes so an A4 letterhead will fit unfolded in a C4 envelope and an A5 piece of paper unfolded in a C5 envelope and that’s it!
The only fly n the ointment is why does a piece of A4 folded to 1/3 A4 fit into what’s called a ‘DL’ envelope? What does it mean if YOU know let us know!
As printers Promotion House buys it’s paper in the ‘SRA’ size range usually SRA2 = 640x450mm, this is an oversized ‘A’ size, so when we print on it we can get the trim marks, and any bleed (part of the design that goes off the page) within the paper so when finally trimmed the job is neat and has a professional finish!
There are other sizes within the metric system ‘RA’ which is slightly smaller than ‘SRA’ and there is also a ‘B’ series. But generally the ‘SRA’ is used for printing and the ‘A’ series are the finished size!
The technical stuff:
- The definition of this size system is ISO216.
- The A0 size which is the corner stone of the paper sizes has an area of 1 Meter Square.
- If you divide the height by the width of any size the square root is 2 which equals 1.4142.
Have fun it’s only paper!
The Print Doctor