PDF Tools

PDF Page Size Converter

Changes every page of a PDF to one of six standard sizes: A4, Letter, Legal, A3, A5 or Tabloid. Each page's content is scaled down or up evenly to fit inside the new page and centred, so nothing is cropped or stretched.

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Process

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Up to 1 files

Target Page Size

How to Use

1Drop one PDF onto the upload area. Only one file is accepted.
2Under Target Page Size, click one of the six buttons: A4, Letter, Legal, A3, A5 or Tabloid.
3Click Convert Page Size.
4Download the result, which is named after the size, for example a4.pdf.

About this tool

Updated October 24, 2026

Content is scaled to fit, never cropped

Each page is scaled by a single factor chosen so the whole page fits inside the new size, then centred on it.

Because width and height are scaled by the same factor, nothing is stretched or squashed. Because the factor is the smaller of the two that would fit, nothing runs off the edge and nothing is cut away. When the old and new shapes differ, the leftover space appears as even margins on two sides — converting a squarer page to a taller one leaves bands at the top and bottom. That is the honest result of fitting one rectangle inside another.

The sizes you can convert to

A3, A4, A5, US Letter, Legal and Tabloid, applied to every page in the document.

That covers the common office and print sizes on both the metric and US sides. A4 is 210 × 297 mm; US Letter is 8.5 × 11 inches; A3 is 297 × 420 mm. There is no custom size box and no way to convert only some pages, so a document with mixed page sizes comes out uniform. Since content is scaled rather than re-flowed, an A3-to-A4 conversion keeps the whole page but makes its content smaller. Converting Letter to A4 adds or changes margins because the two page shapes are slightly different.

Text stays text

Nothing is converted to an image, so the document remains selectable, searchable and sharp at any zoom.

The page content is transformed mathematically rather than redrawn, which means vector graphics and embedded fonts keep their quality at the new size. Photographs inside the page are the one thing that can suffer: enlarging a page enlarges its images, and an image that was just sharp enough on A5 may look soft once it has been scaled up to A3. Shrinking never causes that problem.

When to reach for this

Use it when a printer, a submission portal or a binding process demands one specific paper size.

The usual cases are a document built on US Letter that has to print on A4, or a set of scans at odd sizes that must be uniform before binding. If instead you want to trim white margins away, that is Crop PDF, which changes the visible area rather than the paper size. If you built a PDF from images and got unusual page dimensions, running it through here is the standard way to bring it back to A4.

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Features

Six fixed targets: A4, Letter, Legal, A3, A5, Tabloid
Uniform scaling that keeps proportions; content is centred with blank margins where needed
Applied to all pages; every page in the file gets the same target size
One PDF per run (maxFiles is 1)
No custom width and height option
Runs in your browser; the file is not uploaded

FAQ

Will my content be cropped or stretched?

Neither. The content is scaled by one factor, the smaller of the width and height ratios, so it fits inside the new page and is centred. If the aspect ratio differs, you get empty margins on two sides.

What about a landscape page going onto a portrait size?

The tool does not rotate. A landscape page put onto portrait A4 is shrunk to fit the width and ends up small with large blank space above and below. Rotate the pages first with the Rotate PDF tool if needed.

Do links and form fields move with the content?

They may not. Only the page content is scaled; annotations such as links and form fields keep their original coordinates and can end up out of place. If that matters, check the result or flatten the form first.

Can I choose a custom size?

No. Only the six presets listed on the page are available.

Crop PDF

Trim margins from every page of a PDF by entering point values.

Rotate PDF

Rotate all pages of a PDF by 90, 180 or 270 degrees and download the corrected file.

Flatten PDF

Turn fillable PDF form fields into fixed page content that can no longer be edited.