How to Change PDF Page Size (Resize Pages Free Online)

Not all PDFs come in the size you need. You might have a US Letter document that needs to be A4 for European printing, a presentation slide that needs to fit on standard paper, or a form designed for Legal-size paper that you need on Letter. Changing the page size of a PDF is straightforward once you know where to look.

This guide covers how to resize PDF pages using free online tools, desktop software, and built-in operating system features.

Common PDF Page Sizes

Before resizing, here are the standard sizes you'll encounter:

Size Name	Dimensions	Common Use
A4	210 x 297 mm (8.27 x 11.69 in)	International standard, most common worldwide
US Letter	215.9 x 279.4 mm (8.5 x 11 in)	Standard in US, Canada, Mexico
Legal	215.9 x 355.6 mm (8.5 x 14 in)	Legal documents, contracts
A3	297 x 420 mm (11.69 x 16.54 in)	Posters, large diagrams
A5	148 x 210 mm (5.83 x 8.27 in)	Booklets, small publications
Tabloid (Ledger)	279.4 x 431.8 mm (11 x 17 in)	Newspapers, large format prints

Method 1: Print to PDF (Easiest Built-in Method)

The fastest way to resize a PDF on any operating system is to "print" it to a new PDF with different page settings.

Windows:

Open the PDF in your browser or PDF reader.
Press Ctrl+P to open the print dialog.
Select Microsoft Print to PDF as the printer.
Under Page Setup or Preferences, choose the target paper size (A4, Letter, etc.).
Choose scaling: "Fit to printable area" or "Actual size."
Click Print and save the new PDF.

Mac:

Open the PDF in Preview.
Press Cmd+P to open the print dialog.
Click Show Details if the dialog is collapsed.
Change the paper size in the dropdown (or create a custom size via Manage Custom Sizes).
Click the PDF dropdown in the bottom-left corner.
Choose Save as PDF.
Name and save the resized file.

Method 2: iLovePDF Resize Tool (Best Online)

iLovePDF offers a dedicated PDF resize tool that lets you pick standard sizes or set custom dimensions.

Go to ilovepdf.com/resize-pdf.
Upload your PDF.
Choose a preset size (A4, Letter, Legal) or enter custom dimensions.
Select scaling behavior: fit to page, fill page, or stretch.
Click Resize PDF.
Download the resized file.

Method 3: PDFsam Visual (Best Desktop Tool)

PDFsam Visual (free version available) gives you more control over resizing, including page margins, content scaling, and centering options.

Download and install PDFsam Visual.
Open the app and select Resize.
Add your PDF files.
Set the target page size and scaling options.
Choose output location and click Run.

Understanding Scaling Options

When you change a PDF's page size, you have to decide what happens to the content on each page:

Fit to page: Scales the content to fit within the new page size while maintaining aspect ratio. May add whitespace (margins) if the proportions differ.
Fill page: Scales content to fill the new page entirely. May crop content if proportions differ.
Stretch: Distorts content to fill the new page exactly. Will change the aspect ratio.
No scaling: Keeps content at original size and places it on the new (possibly larger or smaller) page. Content may be clipped or float in whitespace.

Recommendation: Use "Fit to page" for most cases. It preserves the content without distortion.

Batch Resizing Multiple PDFs

If you need to resize many PDFs at once (for example, converting a folder of Letter-size documents to A4):

PDFsam Visual: Add all files, set the target size, and process them in one batch.
PDF24: The online tools at pdf24.org handle batch uploads.
Command line (Ghostscript): For technical users, Ghostscript can batch-resize PDFs with a script. Example command to convert to A4:

Use Ghostscript with the -sPAPERSIZE=a4 flag for batch conversions on Linux and macOS systems.

Common Issues When Resizing

Content gets cut off after resizing

This happens when you shrink a page and use "no scaling" or "fill page." Switch to "Fit to page" scaling to keep all content visible.

The resized PDF has huge margins

When converting between sizes with different proportions (like Letter to A4), margins are normal. Use a tool that lets you crop margins after resizing if the whitespace bothers you.

Text becomes blurry after enlarging

If the original PDF contains raster images (scanned pages), enlarging will make them blurry. Vector-based PDFs (text, shapes) scale cleanly at any size.

Form fields break after resizing

Interactive form fields may shift or become misaligned when page size changes. After resizing a fillable PDF, test all form fields to make sure they still work correctly.

The Bottom Line

For a quick resize, use the print-to-PDF trick built into Windows and Mac. For more control, use iLovePDF's resize tool online or PDFsam Visual on your desktop. Always check the "Fit to page" option to avoid cutting off content.