What size is this?

I can't judge the size of the paper from the pictures you provided. There is nothing to refer to in the picture, so I can't determine the length or width of this paper.

If you can provide more information, such as the ratio of paper to other objects, or the thickness of paper, I may be able to estimate the size of paper more accurately.

According to my experience, the size of this paper is generally between 10 cm and 20 cm. However, this is only an estimate, and the specific size may be different.

If more accurate dimensions are needed, you can use a ruler or other measuring tools to measure the paper.

The following are some common card sizes:

Business card: 9 cm x 5.5 cm

Folding card: 10cm x 20cm

Publicity card: 15cm x 20cm

Greeting card: 10cm x 15cm

You can choose the appropriate size according to your own needs.