SmartPrint

Paper sizes

A4 vs Letter vs Legal

Paper size affects how many sheets you need and whether your printer tray matches. A4 (210 × 297 mm) is the global standard outside North America. Letter (8.5 × 11 in) and Legal (8.5 × 14 in) dominate US home and office printers.

Regional defaults matter

Using the wrong paper size in a tiled layout changes sheet count and final dimensions. A4 is slightly taller and narrower than Letter.

SmartPrint picks a sensible default from your locale but lets you switch before export — always match the paper loaded in your tray.

When to choose Legal or A3

Legal (8.5×14 in) is rarely used for posters but appears in some US document scans. A3 (297 × 420 mm) can reduce tile count when your printer accepts it.

For tiling, target paper is what comes out of your printer — source paper size is what you are trying to reproduce at scale.

Key points

  • A4 — 210 × 297 mm; default for most of Europe, Asia, and Oceania
  • Letter — 8.5 × 11 in (216 × 279 mm); default for US home printers
  • Legal — 8.5 × 14 in; taller US format, less common for posters
  • SmartPrint defaults to A4 for Chinese users and Letter for English users — you can switch anytime

Step by step

  1. Check which paper trays your printer supports.
  2. Open SmartPrint and pick A4 or Letter as target paper.
  3. Upload your file and compare sheet counts for the same poster size.
  4. Export the tiled PDF for the paper you will actually load.
  5. Print at 100% scale so assembled dimensions stay accurate.

Pro tips

  • Buy the paper size your printer manual lists first — usually A4 outside North America and Letter in the US.
  • When sharing tiled PDFs internationally, note which target paper you used in the filename.
  • Preview sheet count when switching between A4 and Letter — the grid is not a 1:1 swap.

Common questions

Is A4 the same as Letter?

No. A4 is 210 × 297 mm; Letter is 216 × 279 mm. They are close but not interchangeable for precise posters.

Which default does SmartPrint use for me?

English defaults to Letter; Chinese defaults to A4. Change it anytime in the paper picker before export.

Choose your paper size

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