# A4 Paper Size Facts

## Dimensions

- A4 size in millimetres is 210mm x 297mm.
- A4 size in inches is 8.3in x 11.7in.
- A4 area in square metres is 0.06237m
^{2} - A4 area in square millimetres is 62370mm
^{2} - A4 area in square feet is 0.671345093ft
^{2} - A4 area in square inches is 96.673693347in
^{2}

## Aspect Ratio

- The aspect ratio (width:height) of A4 paper is 1:1.4142 (1:√2).

## Comparison With Other ISO 216 Sizes

- A4 is one sixteenth of the size of A0.
- A4 is one eighth of the size of A1.
- A4 is one quarter of the size of A2.
- A4 is half the size of A3, having the width of A3 as its height in portrait orientation.
- A4 is twice the size of A5, having the height of A5 as its width in portrait orientation.
- A4 is four times the size of A6.
- A4 is eight times the size of A7.
- A4 is sixteen times the size of A8.
- A4 is thirty two times the size of A9.
- A4 is sixty four times the size of A10.

## Comparison With Non ISO 216 Sizes (Including US Sizes)

- A4 is the closest ISO 216 paper size to US Letter and Legal paper sizes. A4 297mm (11.7") is slightly longer than Letter 279mm (11.0") but slightly shorter than Legal 356mm (14.0"). A4 210mm (8.3") is slightly narrower than Letter and Legal 216mm (8.5").
- A4 is the closest ISO 216 paper size to the old Imperial Foolscap size. A4 297mm (11.7") is slightly shorter than Foolscap Folio 330mm (13.0") and A4 210mm (8.3") is slightly wider than Foolscap 203mm (8.0").

## Weight of A4 Sheets

- A sheet of 80gsm A4 paper weighs 5 grams (0.17637 ounces).
- A sheet of 100gsm A4 paper weighs 6.25 grams (0.22046 ounces).
- A sheet of 160gsm A4 card weighs 10 grams (0.35274 ounces).

More information on paper weights here.

## Envelopes For A4 Paper

- A C4 envelope will take an unfolded sheet of A4 paper. C4 envelopes are sometimes, incorrectly, referred to as A4 envelopes.
- A sheet of A4 paper folded in half by placing the two narrow sides together will fit into a C5 envelope.
- A sheet of A4 paper folded into quarters will fit into a C6 envelope.
- A DL envelope will take an A4 sheet folded into thirds. The DL envelope is the most commonly used business envelope.

Full information on ISO 216 envelope sizes here.

## Untrimmed Sizes To Allow For Print Bleed

- RA4 (Raw format A4) is 105% of the size of A4, thus 215mm x 305mm (8.5" x 12.0").
- SRA4 (Supplementary raw format A4) is 115% of the size of A4, thus 225mm x 320mm (8.9" x 12.6").

More information on raw format and supplementary raw format here.

## Magnification Factors For Reprographics & Photocopying

- Enlarge A4 to A0 using a scale factor of 400%.
- Enlarge A4 to A1 using a scale factor of 283%.
- Enlarge A4 to A2 using a scale factor of 200%.
- Enlarge A4 to A3 using a scale factor of 141%.
- Reduce A4 to A5 using a scale factor of 71%.
- Reduce A4 to A6 using a scale factor of 50%.
- Reduce A4 to A7 using a scale factor of 35%.
- Reduce A4 to A8 using a scale factor of 25%.
- Reduce A4 to A9 using a scale factor of 18%.
- Reduce A4 to A10 using a scale factor of 12.5%.

More about magnification factors for reprographics and photocopying here.