How do I change a PDF's page size, like Letter to A4?
To resize a PDF's page size, drop it into FixDoks's Resize PDF Pages tool, choose a new size such as A4, Letter, Legal, A3, A5 or a custom size in millimetres, pick an orientation, then click Resize PDF. The content is scaled to fit and centred on the new page, and it all happens inside your browser.
Resize PDF Pages at a glance
| Input | One PDF file |
|---|---|
| Output | PDF at the new page size |
| Processing | In your browser; your files are not uploaded |
| Price | Free, no watermark |
| Download | Free Google sign-in |
| Works on | Chrome, Edge, Safari and Firefox on Windows, Mac, Android and iPhone |
How to use Resize PDF Pages
- Drop your PDF onto the box.
- Choose a new page size: A4, Letter, Legal, A3, A5, or enter a custom size in millimetres.
- Pick an orientation (Keep, Auto, Portrait or Landscape) and add a margin if you want extra white space around the content.
- Click Resize PDF and download the file.
What does this tool change?
This tool changes the physical paper size a PDF's pages are defined at, not the file size in kilobytes; if reducing the size of the file itself is your goal, see Compress PDF instead. Resizing is the common fix for a PDF that was made for one paper standard, most often US Letter, but needs to be printed or accepted somewhere that expects A4, or the reverse.
How the content is fitted
Rather than stretching or cropping the page unevenly, FixDoks scales the entire page content proportionally to fit inside the new page size and centres it, so nothing is distorted or cut off. If the new page has a different aspect ratio to the original, for example going from A4 to a square custom size, there will be some extra white space on two sides; you can add a margin on top of that if you specifically want breathing room around the content, for example before binding.
Standard sizes at a glance
| Size | Where it's standard |
|---|---|
| A4 (210 x 297 mm) | Most of the world, including India, UK, Europe. |
| Letter (216 x 279 mm) | United States, Canada. |
| Legal (216 x 356 mm) | US legal and government documents. |
| A3 (297 x 420 mm) | Posters, large diagrams, two-page spreads. |
| A5 (148 x 210 mm) | Booklets, flyers, small print jobs. |
A custom size in millimetres covers anything outside these standards, such as a specific label size or a non-standard notebook page.
Orientation: keep or auto
Keep gives every new page the same orientation as the original page, so landscape pages stay landscape. Auto picks portrait or landscape for each page, whichever lets the content appear largest, which normally matches the original. Choose Portrait or Landscape to force every page the same way, for example to make a mixed document uniform before printing.
What gets preserved and what does not
The visible content stays vector and sharp since it is scaled, not rasterised. However, clickable links and fillable form fields are not carried over to the resized pages, since their exact positions depend on the original page geometry; if you need a resized version of a fillable form, fill it in first with Fill PDF form and flatten it, then resize.
Typical uses
- Converting a US Letter document to A4 before printing in a country that uses A4.
- Standardising a scanned document that has mismatched page sizes across pages.
- Shrinking a large poster PDF down to A4 for a quick desk print.
Tips
If the goal is purely to remove white margins rather than change the page's standard size, Crop PDF is the more direct tool. Check one resized page before processing a long document, since a large aspect ratio change can leave more white space than expected.