How to use
- Choose a PDF; the preview shows the page with the area to be trimmed shaded.
- Enter the millimetres to trim from top, right, bottom and left and choose which pages, or tick automatic white-margin removal.
- Click Download cropped PDF.
Options explained
- How it works
- Each page's CropBox (visible area) is set, so viewers and printers show only what is inside it.
- Automatic margins
- Finds the content area of every page separately and keeps a little space around it — useful when page sizes vary.
Example and units
The margins are entered in millimetres and converted to PDF points, where 1 mm = 72 ÷ 25.4 = 2.835 pt. On an A4 page (210 × 297 mm), trimming 20 mm from the left and right and 25 mm from the top and bottom leaves a visible area of 170 × 247 mm.
Pages are never cropped away completely: if the area left on a page would be narrower or shorter than 10 pt (about 3.5 mm), that page is left unchanged.
Because only the CropBox changes, the page size in the file’s own properties may still show the original dimensions. Viewers and printers use the CropBox, so they show the trimmed size.
Frequently asked questions
Is the trimmed content deleted?
No, only hidden, and software such as Acrobat can restore it. Use PDF redaction to remove sensitive content.
Does it work on rotated pages?
Yes. Top, right, bottom and left follow the page as you see it.
Is my file uploaded?
No. Everything happens in your browser.
Privacy
This tool runs entirely in your browser. Your files and text are processed on your device and are never uploaded to our servers.