OneClickPDF

How to Resize PDF Pages to A4, Letter, or Custom Sizes

Last updated: February 22, 2026

Received a PDF in the wrong page size? Need to convert a Letter-sized document to A4 for European printing, or resize a design proof to a custom dimension? OneClickPDF's resize tool changes page dimensions while intelligently handling the content — with a live side-by-side preview so you can see the result before committing.

Step-by-Step Guide

1

Open the Resize Pages tool

Go to the Resize Pages page on OneClickPDF.

2

Upload your PDF

Drop your PDF onto the upload zone.

3

Choose your target size

Select a preset (A3, A4, A5, Letter, Legal, Tabloid) or enter custom dimensions in points, millimeters, or inches. Set the orientation to Auto, Portrait, or Landscape. Choose how content should be handled: Fit (scale content proportionally to fit the new page) or Center (place content at original size in the center of the new page).

4

Preview, select pages, and download

A live side-by-side preview shows the original page alongside the resized version. Use Select Pages mode to resize only specific pages while leaving others at their original size. When satisfied, download the resized PDF.

Resize Pages

Change PDF page dimensions to A4, Letter, or custom sizes.

Try It Free

Frequently Asked Questions

What's the difference between Fit and Center mode?
Fit mode scales your content proportionally to fill the new page size as much as possible without cropping. Center mode places the content at its original size in the center of the new page — this may add whitespace (if the new page is larger) or crop edges (if it's smaller).
Can I resize only certain pages?
Yes. Switch to Select Pages mode and choose which pages should be resized. Unselected pages keep their original dimensions.
Does resizing affect text quality?
No. OneClickPDF uses vector-based resizing — it changes the page dimensions and scales the content transform without rasterizing. Text remains fully searchable and selectable.
What units can I use for custom sizes?
You can enter dimensions in points (PDF native unit), millimeters, or inches. The tool converts between units automatically.

No other free online tool gives you preset sizes, custom dimensions, content scaling modes, selective page resize, AND a live preview — all without uploading your file. OneClickPDF's resize tool is the most complete option available.

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