How many a4 sheets are there in a pack?

Generally speaking, the standard package of A4 paper is 500 sheets per package and 70 grams per square meter.

The aspect ratio of paper size in group A is √ 2: 1, and then the nearest millimeter value is rounded off. A0 is defined as paper with an area of one square meter and an aspect ratio of √ 2: 1. The following paper sizes, such as A 1, A2, A3, etc. , are defined as the paper with one digit missing is folded in half along the long side and then discarded to the nearest millimeter value.

The size of group B paper is the geometric average of group A paper, with the same number and one less number. Before the popularization of printers, group B paper was mostly used. Group C paper size is mainly used for envelopes.

A4 paper is defined by ISO 2 16, and its specification is 21* 29.7cm (210mm× 297mm). Most countries in the world use this international standard for paper size.

This standard was first incorporated into DIN(DIN 476) by Weimar * * and China in 1922. Although some formats were developed in France at the same time, they were later forgotten. O 2 16 defines three groups of paper sizes: Group A, B and C.C. Paper sizes are mainly used for envelopes.