What Is the Formula for Calculating Paper Size According to ISO 216?

Learn the formula for calculating ISO 216 paper sizes and the dimension ratios for A-series paper formats like A0, A1, and A2.

Published

Video transcript

The formula for calculating paper size is based on the ISO 216 standard. For any `A` series paper size, the area of A0 is 1 square meter. Each subsequent size (A1, A2, etc.) is half the size of the previous one. Dimensions follow the ratio √2:1.

Questions and answers

  1. What is the ISO 216 standard for paper sizes?

    ISO 216 is an international standard defining the sizes of paper sheets in the A, B, and C series, with the A series starting at A0, whose area is exactly 1 square meter.

  2. How do I calculate the dimensions of each A series paper size?

    Starting from A0, each subsequent size (A1, A2, etc.) is half the area of the previous size, maintaining a width-to-height ratio of the square root of 2 to 1.

  3. Why is the ratio √2:1 important for paper sizes?

    This ratio allows paper to be folded or cut in half while preserving the same aspect ratio, which is essential for scaling documents consistently.