How to resize a PDF to A4, Letter, A3 or a custom page size
A form needs A4 but your file is US Letter, or a drawing must be A3. Resize PDF page size converts all pages to the size you pick.
Steps
- Add your PDF.
- Pick New page size (A4, Letter and others) or choose Custom size and enter width and height in mm.
- Choose Scaling: Fit inside the page, keep proportions (default) or Stretch to fill the page.
- Leave Match each page’s orientation ticked so landscape pages stay landscape.
- Download the resized PDF.
Fit or stretch?
Fit is almost always right: nothing is distorted, but you may see empty bands on the sides if the shapes differ. Stretch fills the whole page and can make circles look like ovals. Use it only if you know the proportions already match.
Tips
- Going from Letter to A4 is a small change; A4 to A3 enlarges the page and leaves content proportional.
- For a margin around everything, use Add margin in Shrink mode afterwards.
- Pages that carry a rotation flag keep their orientation; fix sideways pages with Rotate PDF first.
- Resizing changes the paper size, not the file weight. To reduce size, see how to compress a PDF.