pdfMB

Resize PDF

Change the paper size of every page to A4, Letter or any size you need. Your file stays on this device.

  • No uploadYour file stays on this device.
  • Your original stays as it isYou download a new copy. Your file is never changed.
  • Free, no sign-upNo account and no daily limit.

What happens to your file

Everything below happens inside your browser, on your own device. The PDF is never uploaded, so nobody else, including us, can see it.

  1. Your browser reads the PDF into memory and finds the size of every page, including pages that were turned or cropped.
  2. The preview is drawn on your device with pdf.js, the PDF viewer built into Firefox. It uses the same calculation as the real resize.
  3. Each page gets a new paper size. The original content is placed on it with a single scaling instruction, so nothing is redrawn and nothing becomes a picture.
  4. Text keeps its fonts, so it can still be selected, copied and searched. Thai and other scripts look exactly as before.
  5. Links, form fields and comments are moved and scaled together with the content, so they still sit on the right words.
  6. Anything that was hidden outside a cropped page stays hidden. It does not appear in the new white margins.
  7. Pages that are already the size you picked are left untouched.
In short
  1. Choose a PDF
  2. Pick the paper size
  3. Check the preview
  4. Press “Resize” and download

How to change the page size of a PDF

  1. Choose a PDF. pdfMB shows the current size of its pages, for example “Letter portrait · 15 pages”.
  2. Pick the new paper size: A4, Letter, A3, A5, Legal, or type your own width and height in millimetres or inches.
  3. Leave the orientation on “Same as each page” so that landscape pages stay landscape, or force every page to portrait or landscape.
  4. Choose “Scale to fit the paper” to shrink or enlarge the content to the new paper, or “Keep the original size” to change only the paper around it.
  5. Check the preview, then press “Resize” and download the new PDF.

When people use it

Print a US document in Europe or Asia

Letter pages printed on A4 lose a strip at the bottom. Resizing to A4 scales the page so nothing is cut off.

Meet an upload rule

Courts, universities and government portals often accept A4 only. Make every page the size they ask for.

Make a mixed file consistent

Scans, receipts and slides in one PDF often have different sizes. Give them all the same paper size.

Turn A4 into A5 booklets or A3 posters

Scale the whole document down for a handout or up for a poster.

What it can’t do

  • Text does not reflow. The page is scaled as a whole, so making a page much smaller makes the text smaller too.
  • Scaling to fit keeps the shape of the page. If the new paper has a different shape, white space is added on two sides. The content is never stretched.
  • With “Keep the original size”, a paper smaller than the content cuts off the edges.
  • Password-protected PDFs cannot be opened. Remove the password first.
  • A digital signature in the file will no longer be valid, because the file has changed.

Questions about resizing PDF pages

Does resizing lower the quality?

No. The pages are not turned into pictures. The same text and drawings are placed on the new paper, so they stay sharp at any zoom.

Can I still search and copy the text?

Yes. The fonts and the text are kept exactly as they were, including Thai and other scripts.

What is the difference between the two content options?

“Scale to fit the paper” makes the content bigger or smaller so the whole page fits. “Keep the original size” leaves the content at 100% and only changes the paper around it.

What happens to landscape pages?

With “Same as each page”, landscape pages get landscape paper of the size you picked. Choose “Portrait” to make them portrait as well. They are then scaled down to fit.

Is A4 the same as Letter?

No. A4 is 210 × 297 mm and used in most countries. Letter is 216 × 279 mm and used mainly in the US and Canada. A4 is narrower and taller.