Crop & resize PDF
Trim page margins, or resize every page to A4, Letter and more. Runs on your device, nothing is uploaded.
How to use Crop & resize PDF
- 01Drop a PDF onto the upload area.
- 02To crop: drag the yellow box on the page preview, or click Auto-trim margins. Crop all pages the same way, or each page separately.
- 03To resize: switch to Resize pages and pick A4, Letter, Legal, A5, A3 or a custom size in millimetres.
- 04Click Download PDF.
Scanned books come with thick black or white borders, slides exported to PDF have wide margins, and a portal insists on A4 when your file is Letter. Cropping and resizing fixes both without re-scanning or re-exporting anything.
Cropping sets the visible area of each page, so the margins are hidden in every PDF viewer and when printing. Resizing places each page on a new sheet of the size you choose, scaled to fit and centred, with landscape pages kept landscape. Both keep text and drawings as sharp vectors: nothing is turned into an image.
Everything happens in your browser with pdf-lib; the PDF is never uploaded. Auto-trim reads the page background colour from its edges (white, cream or grey) and puts the crop just outside everything that differs from it.
Questions
Is my PDF uploaded?
No. Cropping and resizing happen inside your browser tab and nothing is sent to a server.
Is the cropped part deleted?
It's hidden: every viewer and printer shows only the cropped area, but the content is still in the file. Don't rely on cropping to remove private information.
Will resizing to A4 stretch my pages?
No. Pages are scaled evenly to fit and centred, so their shape never changes. Any difference in shape becomes white space at the sides.
Does it lower the quality?
No. Text and graphics stay as vectors; only the page box and scale change.