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🧰 기타 변환

용지 규격 변환기 (A4 / 레터 / B계열 / JIS)

ISO A0~A10, B계열, C계열, 미국 레터/리걸/타블로이드, 일본 JIS까지 모든 표준 용지 규격을 mm와 인치로 변환하세요.

배율 A → B:
크기mmcm인치면적 (cm²)
계산 원리

ISO A 시리즈는 A0 = 841 × 1189 mm(면적 1 m², 비율 √2)에서 시작합니다. 다음 사이즈로 갈 때마다 긴 변이 절반이 됩니다. B 시리즈는 연속된 두 A 사이즈의 기하평균이며, C 시리즈는 A를 담을 수 있는 크기로(봉투용) 만들어집니다.

배율은 min(B.가로/A.가로, B.세로/A.세로)입니다 — A를 잘리지 않게 B 안에 맞출 수 있는 최대 배율입니다. 1인치 = 25.4 mm.

계산 원리

Two dropdowns, a fifty-entry lookup table and one ratio. The list holds ISO A0–A10, ISO B0–B10, ISO C0–C10, JIS B0–B10 and six US sizes — Letter, Legal, Tabloid, Executive, Statement and Ledger — all stored in millimetres. Scale A → B is min(B.width ÷ A.width, B.height ÷ A.height) × 100, the largest uniform reduction that fits A entirely inside B. A4 onto US Letter comes out at 94.1%.

Order matters, because A is the source and B is the destination; swapping the two gives a different percentage. The table underneath prints both sizes in millimetres, centimetres, inches at 25.4 mm to the inch, and area in square centimetres, which is the quickest way to see A-series areas halving step by step down from A0's one square metre. The defaults are A4 against US Letter, the comparison most people arrive for.

The percentage is a geometric fit, not a print setting. It ignores your printer's unprintable margin, so scaling A4 artwork to exactly 94.1% on Letter can still clip at the edges — most drivers quietly apply their own shrink on top. The dimensions are the published whole-millimetre values, themselves rounded from the underlying √2 geometry, and every size is listed portrait except US Ledger, stored as 431.8 × 279.4 mm landscape.

자주 묻는 질문

What percentage do I use to print A4 on US Letter?

94.1%, which is what the tool returns with A4 as size A and US Letter as size B. Going the other way, Letter onto A4, gives 97.3%. Both are fit-to-page factors that keep the entire page visible without cropping anything.

Is A4 bigger than US Letter?

A4 is narrower and taller: 210 × 297 mm against 215.9 × 279.4 mm. By area A4 wins, 623.7 cm² to 603.2 cm². Because the mismatch runs in both directions, neither prints on the other without some scaling.

What is the difference between ISO B5 and JIS B5?

They are not the same sheet. ISO B5 is 176 × 250 mm, defined as the geometric mean of A4 and A5. JIS B5 is 182 × 257 mm, derived from a larger area rule used in Japan. Both appear in the dropdown.

Which envelope size fits an A4 letter?

C4 at 229 × 324 mm takes an unfolded A4 sheet, C5 at 162 × 229 mm takes A4 folded once, and C6 at 114 × 162 mm takes it folded twice. The whole C-series is dimensioned to swallow its matching A size.

How does the A-series actually work?

A0 is 841 × 1189 mm, one square metre at a √2 aspect ratio. Halving the long side gives each next size down, all the way to A10 at 26 × 37 mm, and the ratio is preserved so scaling between them never distorts proportions.

다른 이름

paper size convertera4 to letterpaper size chart

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