دليل مقاسات الورق القياسية: A4، A3، B5، Letter بالسنتيمتر والبوصة

1. Overview of ISO 216 International Paper Standards

The ISO 216 standard governs paper sizes used across most countries globally. Designed based on the 1:√2 (approx 1:1.4142) aspect ratio, folding the paper in half maintains the exact same aspect ratio.

2. ISO A-Series Dimensions Reference Table

Format	Millimeters (mm)	Centimeters (cm)	Inches (in)
A4 (Standard)	210 × 297 mm	21.0 × 29.7 cm	8.3 × 11.7 in