Use the free PDF Page Size Changer below: choose a PDF, adjust the settings, and download your edited PDF. Your PDF never leaves your browser — all processing happens on your device, and nothing is uploaded to any server.
Why Change a PDF’s Page Size?
PDFs arrive in all sorts of page sizes. A document made in the United States is often Letter size. A document made in Europe is usually A4. A contract might be Legal size, and a booklet might be A5. When you print a mixed collection, or submit a document to an office that requires a specific size, those differences become a problem. Pages come out scaled, cut off or surrounded by wasted white space.
The PDF Page Size Changer on this page fixes the page size in your browser, free, with no sign-up. You choose A4, Letter, Legal, A5 or a custom size in points, and the tool rewrites the PDF with the new dimensions. Your PDF never leaves your device.
How the Tool Works
PDF pages have a size stored in points, where one point is one seventy-second of an inch. A4 is 595 by 842 points. Letter is 612 by 792 points. Legal is 612 by 1008 points. The tool uses pdf-lib to set each page’s size to the dimensions you choose. You can apply the change to every page, or to selected pages using a list like 1,3-5.
One honest limitation matters here. Changing the page size does not rescale or reflow the content. Text, images and tables stay exactly where they were, at their original size, measured from the bottom-left corner of the page. If you enlarge a page, the content sits in the same corner with more empty space around it. If you shrink a page, content near the top or right edge may run past the new edge. This is the same behaviour as the page-size tools in desktop PDF software, and it is the correct behaviour for a tool that must not alter your content.
How to Change Page Size
Choose a PDF and pick the new size. A4 is the right choice for most European offices, schools and official forms. Letter is the right choice for most American ones. Legal suits long contracts. A5 suits small booklets and handouts. If you need something else, choose Custom and enter the width and height in points. One inch equals 72 points, so a 6 by 9 inch page is 432 by 648 points.
Leave the pages field blank to change every page, which is what most people want. Use the pages field when only part of a document needs changing, for example when a single oversized diagram page should match the rest. Then save and download the new PDF.
Common Uses
Students and job applicants often need to submit documents in A4, even when their source program defaults to Letter. Offices standardising an archive often need every file in one size before printing. Print shops ask for exact page sizes because their machines are set up for them. In all of these cases, a quick page-size change saves re-exporting the whole document from its original program, which may no longer be available.
Teachers preparing handouts also benefit. A worksheet designed for A4 prints wrong on Letter paper if the sizes are mixed up, with margins shifting and content drifting. Setting the page size explicitly removes that uncertainty before the file reaches the printer.
Checking the Result
After downloading, open the new PDF and check its page size in your reader’s document properties. Then look at the pages themselves, especially the first and last. If content is cut off at the top or right, you shrank the page too far for that content, and you should go back to a larger size. If there is a lot of empty space, that is expected when enlarging: the content has not moved, and the extra space is simply the new, larger page.
If you need the content itself resized to fit the new page, that is a different job, closer to re-laying out the document. For that, the honest route is to change the size in the original program and export again. This tool is for the very common case where the size label is wrong but the content is fine.
Privacy
Your PDF never leaves your browser. All processing happens on your own device with pdf-lib. Nothing is uploaded, nothing is stored, and no account is needed.
Frequently Asked Questions
Will my text move or reflow? No. Text stays at its original position and size. Only the page dimensions change.
What if my PDF has mixed page sizes? The tool sets every selected page to the size you choose, so a mixed document becomes uniform.
Can I change just one page? Yes. Enter that page number in the pages field.