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Add Page Numbers to PDF

Stamp page numbers with a live preview.

Crop PDF

Trim margins off every page, by hand or automatically.

Dark Mode PDF

Invert a PDF's colours for comfortable night reading.

Resize a PDF to A3

About this option

A3 is twice the area of A4 — the format of posters, architectural sheets, wall charts and large spreadsheets. This preset opens the page-size tool on A3 with Fit scaling, enlarging each page to fill the bigger sheet without distorting it.

When to use it

  • Sending a drawing or poster to a large-format printer
  • Enlarging an A4 chart so it can be read from a distance
  • Preparing pages for an A3 office printer

How to use it

  1. 1Drop the PDF — A3 with Fit scaling is already selected
  2. 2Switch to Fill if you want the page to cover the sheet completely
  3. 3Check the preview and click Resize
  4. 4Download the A3 PDF

Frequently asked questions

Does enlarging reduce quality?

Vector text and graphics stay sharp. Embedded photographs are not re-sampled, so low-resolution images will look softer at A3.

What are the dimensions of A3?

297 × 420 mm, or 11.7 × 16.5 inches.

Can I shrink A3 back to A4?

Yes. Use the Resize PDF to A4 preset on the A3 file.

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