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標準規格
2026-08-14
4 min read
標準用紙サイズガイド：A4・A3・B5・レターの実寸（cm・inch）一覧表
国際標準ISO 216規格（A/Bシリーズ）および北米ANSIレター規格のセンチ、ミリ、インチ単位の寸法表を確認できます。
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 |
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