# What is the size of A4?

We all looked at the album sheet of A4 paper. Sometimes it is necessary to find out what the size of A4 is, to within millimeters.

The size of A4 is interesting to children in physics lessons,mathematics, geometry, drawing and not only students, but also university students. So, in the absence of a ruler with an A4 sheet, you can measure the size that is needed. Knowing its dimensions, it is easy to calculate the parameters that are given in the drawing tasks or draw a drawing.

What is the size of A4? The dimensions of the A4 sheet are 210x297 mm, the diagonal is 364 mm. And in centimeters, the A4 format is as follows: 21cm x 29.7cm. If you compare with the size of A3, then the size of the sheet A3 is 297 x 420 mm., That is exactly twice as large as A4. A4 is a landscape album. A3 is a newspaper sheet.