Runs in your browser with pdf.js and pdf-lib
Resize PDF Pages Online — to A4, Letter or any size, without distorting the content
Change the paper size of every page or just some, choose how the content fits, and add margins. Each page shows its new size live, so you see the result before you save.
- PDF files aren't uploaded to our server
- A4, Letter, A3, A5 or custom
- Live preview of the new size
- Text stays sharp and selectable
Pick a paper size and see every page on it
Add a PDF, choose the size, fit and margins. The pages below show the result as you change settings.
Drop your PDF here
or browse — one PDF, any number of pages
Pages at their new size
Dashed lines show the margins. Click a page to see it full size.
How resizing actually works
Resizing is two decisions, not one
The new paper size, and what happens to the content that's already on the page. Mixing them up is where most bad results come from.
A new sheet, then a placement rule
A US Letter report that has to go out on A4, a large drawing that should print on A3, scanned receipts of every shape that need one size: each needs a new paper size, but not every document wants its content handled the same way.
The tool changes the paper size of the pages you choose and places the existing content on it with the rule you pick. Text and drawings are scaled, not turned into pictures, so they stay sharp and selectable; links and form fields move with them. pdf.js draws the previews and pdf-lib changes the file, both in your browser tab, so your PDF isn't uploaded to our server.
What you can set
Size
A4, Letter, A3, A5, Legal and Tabloid, any width and height in mm, cm, inches or points, or the same size as now to only add margins.
Orientation
Portrait, landscape, or match each page, so wide pages stay wide.
Fit, fill, stretch or keep scale
Four placement rules, shown live on every page before you save.
Margins and pages
One margin or one per side, on all pages, typed pages, or pages you pick in the grid.
How to resize PDF pages in four steps
The fit rule matters as much as the size: it decides what happens to the content.
Add your PDF
Drop a PDF onto the upload area, or click Select PDF. Every page appears already on A4, the default size, so you see the effect straight away.
The file bar shows the current size of page 1.
Choose the size and fit
- A preset like A4 or Letter, or Custom with your own numbers.
- Portrait, landscape, or match each page.
- Fit, Fill and trim, Stretch, or Keep original scale.
Add margins, check the pages
Set a margin if the content needs room from the edges, and pick which pages to change. Open any page full size to check it.
Pages you leave out keep their size.
Save and download
Click Resize PDF. Page through the saved file, which is drawn from the new PDF itself, rename it if you like, and download.
From one paper size to another, cleanly
A US Letter document resized to A4 with Fit.
Settings for common resizing jobs
A starting point for each. The live preview shows the outcome before you save.
| Job | What matters | Settings to try |
|---|---|---|
| US Letter to A4 | Nothing cut off, nothing stretched. | A4, Match each page, Fit. |
| A4 to US Letter | Same, in the other direction. | Letter, Match each page, Fit. |
| Scans of different sizes | Every page the same size for printing. | A4, Portrait, Fit, 5 mm margin. |
| Large drawing for a normal printer | The whole drawing on one sheet. | A3 or A4, Match each page, Fit. |
| Room for binding or hole punching | Space on the left edge. | Same as now, Fit, Set each side separately with a left margin of 15-20 mm. |
| A5 booklet pages | Smaller pages, text still readable. | A5, Portrait, Fit; check small print full size. |
| Slides that should fill the page | No white bands. | Landscape, Fill and trim. |
| One landscape table in a portrait report | Only that page changes. | Pages… with its number, Landscape, Fit. |
Fit rules explained
Same size, four different results
What each rule does to a US Letter page going onto A4.
Fit
Scaled to 97% so the full width fits; a thin white band appears top and bottom. Nothing is lost. The safe default.
Fill and trim
Scaled to 106% so the full height is covered; a strip at the left and right edges is trimmed. Good for slides and photos.
Stretch
Width 97%, height 106%: the page fills A4 exactly, slightly taller than before. Fine for small changes, visible on big ones.
Keep original scale
Stays at 100%, centered: about 3 mm trimmed from each side, extra paper top and bottom. Use it to add paper, not to shrink.
When the resized file doesn't look right
Identify the problem, then use the matching fix.
A wide page came out tiny
A landscape page was fitted onto a portrait sheet.
Choose Match each page, or Landscape for that page.
Text looks squashed
Stretch was used between sizes of different shape.
Use Fit instead. It keeps the proportions.
Edges are cut off
Fill and trim or Keep original scale was used on a smaller or differently shaped sheet.
Use Fit. Nothing is trimmed with Fit.
"Margins leave no room" message
The margins add up to more than the page's width or height, often from typing mm values while the units are inches.
Check the Units box, then lower the margins.
Some pages didn't change
Pages… or Pick below was chosen, and those pages weren't included.
Check the label under each page: it says the new size or "Keeps its size".
A password-protected PDF won't open
Encrypted PDFs can't be changed by the in-browser PDF libraries.
Remove the password with Unlock PDF, then add the unlocked copy.
The right size on the first try
A working order that avoids a second round.
Start with Fit and Match each page
Nothing is cut, stretched or shrunk onto the wrong orientation. Change only what the preview shows is wrong.
Check the units first
A margin of 10 is a thin line in points and most of the page in inches. The label next to Margin shows the unit in use.
Keep a small margin for printing
Many printers can't print to the very edge. 5 mm keeps content clear of that strip.
Read the smallest text when shrinking
Going to A5 scales text down to about 70%. Open the busiest page full size before you save.
Resize before numbering
If you'll add page numbers, resize first so the numbers sit at the right distance from the new edges.
Keep the original
This tool never changes it, so you can try another size or fit rule later.
Common questions about resizing PDFs
If something's not covered here, the troubleshooting section above likely has it.
Does this tool upload my PDF to a server?
No. The previews and the resizing both run in your browser with pdf.js and pdf-lib. Your PDF is read on your device and is not uploaded to the AllInOneTools server.
How do I change a US Letter PDF to A4?
Add the PDF, choose A4, keep Match each page and Fit, then click Resize PDF. The content is scaled to about 97% so the full width fits, with nothing cut off or stretched.
Will resizing make text blurry?
No. Text and drawings are scaled as they are, not turned into pictures, so they stay sharp and selectable. Photos keep their pixels, so a photo made much larger can look softer, as with any enlarged image.
What happens to landscape pages?
With Match each page, landscape pages get the landscape version of the size you chose, so wide tables and slides aren't shrunk onto a tall page. Choose Portrait or Landscape to force one orientation for every page.
Can I resize only some pages?
Yes. Choose Pages… and type numbers or ranges such as 1-3, 7, or choose Pick below and tap Resize on the pages you want. Every other page keeps its size.
Can I add margins without changing the paper size?
Yes. Choose Same as now as the size and set a margin. The content is scaled down slightly to leave that space, which is useful for binding or hole punching.
Are links and form fields kept?
Yes. The pages are resized inside the original file, so links, form fields and bookmarks are kept, and links and fields move with the content on resized pages. Your original file is not changed.
Build notes
The write-up on resizing PDFs in the browser
Because the resizing runs client-side, I wrote a tutorial on building a browser-based PDF resizer with JavaScript.
How to Build a Browser-Based PDF Resizer Using JavaScript
A step-by-step tutorial on changing PDF page sizes client-side with JavaScript.