How to Resize PDF Pages to A4, Letter, and Custom Sizes
Need to change your PDF from A4 to Letter, or scale pages to fit a specific size? Learn how to resize PDF pages while keeping content sharp and properly positioned.
Why Resize PDF Pages?
PDF pages can be any size, and mismatches cause real problems: a US Letter document printed on A4 paper has incorrect margins; a 16:9 slide deck needs reformatting for A4 handouts; scanned pages came out at non-standard dimensions and need standardising.
Understanding the distinction between scaling (zooming content to fit a new size) and resizing (changing the page boundary without scaling content) is key to getting the right result.
Common PDF Page Sizes
| Size | Dimensions | Common Use |
|---|---|---|
| A4 | 210 × 297 mm | Europe, worldwide |
| US Letter | 215.9 × 279.4 mm | North America |
| US Legal | 215.9 × 355.6 mm | Legal documents |
| A3 | 297 × 420 mm | Large format |
| A5 | 148 × 210 mm | Booklets |
Method 1: ToolsofPDF
- Go to Resize PDF
- Upload your PDF
- Select target size: A4, Letter, Legal, or custom dimensions
- Choose Scale content to fit or Keep content size (change page boundary only)
- Click Resize → download
Scale content: Text and images zoom to fill the new page. Aspect ratios may change slightly.
Keep content size: Content stays the same scale; the page boundary changes. May leave white space or crop edges.
Method 2: Print Scaling (Any Viewer)
The simplest way to rescale to a different paper size:
- Open the PDF in any viewer
- File → Print
- Change paper size to your target (A4 or Letter)
- Enable Fit or Scale to fit
- Print to Microsoft Print to PDF (Windows) or Save as PDF (Mac)
Content scales automatically to fit the new page dimensions.
Method 3: Adobe Acrobat Pro
Change page boundary (no scaling):
- Tools → Print Production → Set Page Boxes
- Set media box size
- Apply to selected pages or all pages
Scale content to fit new size:
- File → Print → Adobe PDF printer
- Set target paper size and enable Scale to fit paper
- Print to a new PDF file
Scaling vs Cropping vs Adding White Space
Scaling: Enlarge or reduce all content proportionally. Used to convert between A4 and Letter.
Cropping: Removes page edges. Content outside the crop box is hidden (not deleted). Used to remove unwanted margins.
Adding white space: Increases page size surrounding content with white space. Used when a page must be a specific size but content is smaller.
Converting Between A4 and US Letter
A4 and Letter are close in size (A4 is slightly taller and narrower). Scaling between them reduces content to about 94% of original — fully readable, with small margins adjusting.
For most business documents this difference is negligible. Use the Print to PDF method with Scale to fit for a clean result.
Resizing a Single Page in a Multi-Page PDF
- Split PDF to extract the pages needing resizing
- Resize the extracted pages
- Merge PDF to rejoin them with the rest of the document
Frequently Asked Questions
Will resizing affect PDF text quality? If done by scaling vectors (text and SVG), quality is preserved at any size. If the tool rasterises the page to an image first, text may look soft — choose a vector-preserving tool.
Can I resize to custom dimensions? Yes — ToolsofPDF supports custom width and height input in mm or inches.
Will form fields and annotations scale? When scaling via Print to PDF, annotations usually scale. Interactive form fields may not — flatten the form before resizing.
Summary
Use ToolsofPDF for quick online page resizing, or Print to PDF in any viewer for easy scaling between sizes. Choose between scaling content proportionally or just adjusting the page boundary. For mixed-size pages, split → resize individually → merge back together.