Crop PDF

How to crop a PDF

1. Drop your PDF onto the upload area; the first page renders as a preview with a draggable rectangle.
2. Choose an aspect ratio (Free, 1:1, A4, Letter) and drag the rectangle to mark what to keep.
3. Choose whether to apply the crop to all pages or just the first, and whether to remove the cut-off area (the default) or keep text selectable.
4. Click Crop and download to get a new PDF with each cropped page the size of the crop rectangle.

Common uses

• Trimming the white margins from a scanned document so the body fills more of the page. Combine with compress PDF to shrink the file too.
• Cutting a single content area out of a multi-column report for archiving or quoting.
• Cropping an oddly proportioned PDF to A4 or Letter proportions, so it fills the sheet when printed with fit to page.
• Preparing a tight extract before converting the page to an image for use on the web.

Technical specification

• Algorithm or formula: The first page is rendered to a canvas via pdfjs-dist. The user-drawn rectangle is converted to PDF user-space points (1/72 inch) with the inverse of pdf.js's page viewport (convertToPdfPoint), which handles page rotation, CropBox insets, and offset page origins. Remove the cut-off area (default): pdf.js renders only that area of each cropped page at 216 dpi, and the JPEG becomes the page in a new PDF. Keep text selectable: the rectangle is written as both the page MediaBox and CropBox (ISO 32000-1 §14.11.2), and the page thumbnail and the comments and links wholly outside it are removed.
• Browser API or library: pdfjs-dist for rendering the preview and the cropped pages, pdf-lib for writing the output.
• Input limits: PDF up to 100 MB.
• Output: A new PDF with the same page count and order. In Remove mode it is a new PDF of images for the cropped pages (text no longer selectable, links and form fields dropped), with uncropped pages copied with their text. In Keep text selectable mode the pages keep their content streams, and each cropped page is resized by setting both its MediaBox and CropBox, so every viewer and printer treats the cropped region as the page while the cut-off area stays in the file.
• Known limitations: One crop rectangle is applied to all selected pages. Only pages with the same size, position, and orientation as the previewed first page are cropped; the tool counts and reports the others, which it leaves uncropped. Remove mode rasterizes only the selected area: it is not redaction of content inside the area you keep. Encrypted PDFs must be unlocked first.

Frequently asked questions

How does PDF cropping work?

By default the tool removes the cut-off area: each cropped page is rebuilt as an image of the selected area, so the rest of the page is not in the file, and its text is no longer selectable. With Keep text selectable, it sets each page's MediaBox and CropBox to the rectangle instead; the content outside stays in the file, which is why such a PDF can be uncropped by another tool.

Will cropping reduce the file size?

With Keep text selectable, usually not by much: the content streams are still there. With the default, Remove the cut-off area, a text PDF usually gets much larger (about 1 MB per dense A4 page), while a scanned PDF may shrink.

Can I apply different crops per page?

This tool applies one rectangle to all pages or just the first. For varying crops, split the PDF first and run the tool on each part.

Is my PDF uploaded anywhere?

All cropping runs in your browser using pdfjs-dist for rendering and pdf-lib for writing. Our servers are not involved at any point.