About this tool
Convert a PDF to a different paper size — Letter to A4, A4 to A5, or any custom width and height in millimetres. Each page's content is scaled to fit the new dimensions (preserving the aspect ratio and centering it), or stretched to fill the page exactly if you prefer.
The conversion is fully vector-based: pages are embedded and rescaled with pdf-lib, so text and line art stay perfectly sharp — nothing is rasterized. It all happens in your browser, meaning your file never leaves your device and nothing is uploaded.
By default the target size follows each page's orientation, so landscape pages become landscape A4 rather than being squeezed into portrait. Untick the orientation option to force every page into the exact target dimensions.
Frequently asked questions
Does resizing blur the text?
No. The pages are rescaled as vectors with pdf-lib rather than being converted to images, so text, lines and graphics remain crisp at any zoom.
What is the difference between fit and stretch?
Fit scales the content uniformly to fit inside the new page (keeping proportions, centered, possibly with small margins); stretch distorts it to fill the page exactly.
Is my PDF uploaded to a server?
No. Everything runs locally in your browser — your file never leaves your device.
Can I use a custom page size?
Yes — choose “Custom” and enter the width and height in millimetres (10–5000 mm), and every page is rebuilt at those dimensions.