A3 Paper Size in Inches: Dimensions, Uses, and Printing Tips
A3 paper measures 11.69 × 16.54 in (297 × 420 mm). Learn when it fits better than A4 and how to print it without scaling mistakes.
A3 paper measures 11.69 × 16.54 inches (297 × 420 mm). It is larger than A4, smaller than A2, and usually chosen for posters, folding diagrams, visual worksheets, and office layouts that need more room than standard printer sheets.
Key dimensions
| Item | Value |
|---|---|
| Width | 297 mm / 11.69 in |
| Height | 420 mm / 16.54 in |
| Nearest smaller size | A4 |
| Nearest larger size | A2 |
When it makes sense
Use A3 when a page feels cramped on A4 but a plotter size would be excessive. Typical workflows include classroom posters, two-page spreads, architecture markups, and process maps that need larger labels and clearer spacing.
What to watch next
Compared with A4, A3 gives you exactly twice the area. Compared with A2, it stays much easier to feed through office printers and copy machines. That middle position is the real reason A3 remains practical.
Printing tips
Before printing, confirm that the driver is set to A3, disable automatic scaling, and run one sample page first. The most common failure is sending an A3 PDF to a Letter or A4 tray and letting the printer shrink it.
Useful PaperGens pages
Quick FAQ
What is the exact size? Use the figures in the table and match them in the PDF and printer driver.
Should I print at actual size? Yes, unless you intentionally want a reduced proof copy.
What is the biggest mistake? Letting the printer or PDF viewer auto-scale the job to the wrong sheet.