Common paper sizes:

A4:

The most popular paper sizes when it comes to printing is A4. A4 is the most used paper size in the world and a format and size that consumers are familiar with. The dimensions of an A4 page are 297mm high x 210mm wide (11.69 inches x 8.27 inches).

A5:

A5 is the runner up when it comes to the most popular paper size. An A5 is half an A4 page and is the preferred size when it comes to leaflets printing, booklet printing etc. An A5 page has dimensions of 210mm high x 148mm wide (8.27 inches x 5.83 inches).

A3:

Another popular size which can be on the larger size but none the less offers great visual impact is A3. The dimensions for A3 pages are 297mm high x 420mm wide (11.69 inches x 16.54 inches) or double the size of an A4 sheet.