A4 Paper Size in Inches, Millimeters and Pixels
A4 is a portrait sheet 210 mm wide and 297 mm tall. Use these values when preparing forms, graph sheets or PDFs whose physical dimensions matter.
| Measurement | Portrait dimensions |
|---|---|
| Millimetres | 210 × 297 mm |
| Centimetres | 21 × 29.7 cm |
| Inches, calculated | 8.2677 × 11.6929 in |
| PDF points, calculated | 595.276 × 841.890 pt |
Fit a form inside a real content box
A 10 mm layout inset on all four sides leaves 190 × 277 mm. A form that is 195 mm wide does not fit that box at 100%: reducing it to 190 mm gives 190 ÷ 195 = 97.44%. A printed 50 mm field would then be about 48.72 mm. Reduce the form’s layout or change the allowed inset if the field must keep its size.
What can change when you print
A4 and Letter are close enough to confuse in a print dialog. A4 is 5.9 mm narrower and 17.6 mm taller. On Letter, Actual Size can clip an A4 design near the top or bottom; Fit changes its scale. Check the PDF page size separately from the loaded paper.
Set up one sample first
- Create or inspect the PDF at the intended millimetre dimensions. Landscape swaps width and height; it does not change the paper size.
- Load matching paper, choose the correct tray and paper type, then check the application and driver settings.
- Use Actual Size for measured layouts. Use Fit only when an intentional reduction or enlargement is acceptable.
- Print one sample and measure a known reference before printing or cutting the remaining copies.
Does this paper have a pixel size?
Paper has physical dimensions. At a chosen 300 pixels per inch, a raster image covering this portrait sheet would be approximately 2,480 × 3,508 pixels. That is a calculation at one chosen resolution, not a fixed property of A4 or a guarantee of print quality. Vector text and lines work differently.
Sources and method
- ISO 216:2007: the scope of the ISO A and B series. Nominal millimetre dimensions are used; rounded inch values do not redefine the sheet.
- NIST: SI units of length: the exact conversion of one inch to 25.4 millimetres. Inch and point values below are calculated from the stated nominal dimensions.
- Adobe Acrobat: adjust page size for printing: Actual Size, Fit and the difference between the page and the printable area.