learn.howToCalculate
learn.whatIsHeading
ISO 216 defines the A-series paper sizes (A4, A3, A0...) using a √2:1 ratio so each size is exactly half the area of the one above. A4 (210×297mm) is the global standard.
Formel
Trin-for-trin guide
- 1A0 = 841×1189mm (exactly 1m² area)
- 2Each subsequent size = fold in half along long edge
- 3√2:1 aspect ratio preserved throughout the series
- 4US Letter = 216×279mm (slightly different ratio)
Løste eksempler
Ofte stillede spørgsmål
What is Paper Size?
ISO 216 defines the A-series paper sizes (A4, A3, A0. ) using a √2:1 ratio so each size is exactly half the area of the one above
How accurate is the Paper Size calculator?
The calculator uses the standard published formula for paper size. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Paper Size calculator use?
This calculator works with inches, square metres. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Paper Size calculator use?
The core formula is: A0 = 841×1189mm (exactly 1m² area). Each step in the calculation is shown so you can verify the result manually.
Klar til at beregne? Prøv den gratis Paper Size Converter-beregner
Prøv det selv →