pdf tool
Crop PDF margins online
Drag across the page to mark the area to keep, or type how many millimetres to trim from each edge, and save a PDF whose pages show only that area. Fit to the content finds the white space around the printed area for you.
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- Runs on your device, nothing is uploaded
- Free, no sign in
- No watermark, no file limit
How it works
- 1
Open the PDF
Choose the file or drop it on the box. The first page is drawn large; with several pages, tap a thumbnail above it to work on another.
- 2
Mark the area to keep
Drag across the page to draw the area to keep, or type Top, Right, Bottom and Left margins in millimetres. Fit to the content trims the white space around whatever is printed, leaving 3 mm.
- 3
Choose the pages
Every page applies the same margins to the whole file; This page only crops just the page on screen. Margins too big for any page are flagged by page number.
- 4
Crop and save
Press Crop and save to download the cropped copy. The message underneath gives the size the page now shows.
What cropping a PDF actually does
Every PDF page has a media box, the full sheet, and can have a crop box, the part a reader shows and prints. Cropping here sets that crop box and nothing else. The text, images and vector shapes outside it stay in the file exactly as they were, which is why cropping is instant, keeps full quality and can be undone by any editor that resets the crop box. It is the same mechanism print software uses for trim and bleed, defined in the PDF standard since its first versions.
Trimming white space from slides, scans and exports
The common reason to crop is wasted margin. A slide deck saved as A4 PDF has wide bands of white above and below each slide; a scanned receipt sits in the corner of a full letter page; a chart exported from a spreadsheet arrives with a page of nothing around it. Fit to the content renders the page, finds the outermost marks and sets the margins to them, less 3 mm so nothing touches the edge. Check the result against the drawing, because faint background tints or page borders count as content.
Rotated and mixed size pages
Margins are always measured as you see the page on screen, so Top means the top of the page as it reads, even when the file stores that page turned 90 degrees. The tool converts each margin to the right edge of the stored page before setting the crop box. When Every page is chosen on a file with mixed sizes, each page loses the same millimetres from each edge, and any page too small for the margins is named so you can switch to This page only. The PDF is read and rewritten in your browser; nothing is uploaded and nothing is stored, ever.
Checking a cropped poster
After cropping a poster or flyer PDF, run it through the A0 poster checker or the PDF page size checker, which read the page boxes and report the size the file now presents. A poster built in OneCraft starts at one of two sizes, A0 portrait or A0 landscape, so the board is laid out at its print shape from the start.
Limits worth knowing
Cropping hides content but does not remove it: anyone can reset the crop box and see what was outside, so never use it to redact. Some print workflows and older viewers ignore the crop box and use the media box. Trim and bleed boxes larger than the new crop are clipped to it by readers. Encrypted files are refused with a message.
Limits
- Cropping sets the crop box; the content is still in the file, and a viewer that ignores crop boxes shows it.
- With Every page chosen, the same margins in millimetres are trimmed from each page, so pages of different sizes keep different areas.
- A crop that would leave less than 10 mm of any page is refused, and an encrypted PDF cannot be rewritten here.
What it does not do
- It does not delete the content outside the crop, so it is not a way to hide confidential text.
- It does not resize or scale pages to a new paper size.
- It does not upload the file.
Questions people ask
Is cropping a PDF the same as redacting it?
No. Cropping only changes which part of the page is shown; the content outside the crop box is still in the file, and anyone with a PDF editor can reveal it again. To remove confidential text or images for good, use a redaction tool that deletes the content itself, then check the result by searching the file for the removed words.
Why does my cropped PDF look uncropped in another program?
Because that program reads the media box, the full sheet, instead of the crop box. Most readers and browsers respect the crop box, but some print drivers, older viewers and image converters do not. If a recipient needs the crop to be permanent, print the cropped file to a new PDF or convert the pages to images after cropping.
Can I crop different pages by different amounts?
Yes, one page at a time. Choose This page only, pick the page from the thumbnails, set its margins and save, then open the saved file and repeat for the next page. Every page applies one set of margins to the whole document, which suits scans and slide exports where every page has the same white border.
Does cropping make the PDF file smaller?
Not noticeably. The content outside the crop stays in the file, so the size barely changes, and it can even grow by a few bytes for the new crop boxes. To make a file smaller, use a compression tool. To make the trimmed content actually leave the file, the pages would need to be redrawn, which this tool does not do.
How many millimetres should I trim from a scanned page?
Start with Fit to the content, which measures the actual white border on the page you are looking at and keeps 3 mm around the printed area. Scanner glass often leaves a grey edge of 2 to 5 mm, which counts as content, so add a millimetre or two by hand if a dark line remains along one side.
Build the poster at the right size
Take what you made here into posters.
Create a poster with OneCraftMore tools like this
- A0 poster checkerDrop a poster PDF and get bleed, trim and safe margins drawn on the artwork, with image density, fonts and type size checked against A0. Nothing is uploaded.
- PDF page size checkerDrop a PDF and read a print report: every page size named against ISO 216 and ANSI, trim box against media box, bleed in millimetres, rotation and clearance.
- Reorder PDF pagesReorder PDF pages in your browser: drag page thumbnails into a new order, or type it, then save. Form fields and links between pages are kept. No upload.
- Add a watermark to a PDFAdd a watermark to a PDF in your browser: DRAFT, CONFIDENTIAL or any text, diagonal or flat, in your size, colour and opacity, on every page or a range.
- Rotate PDFEach page turns in place as you tap it, and sideways pages are turned upright for you. The turn is written into the file, not just the view.
Background reading: the question page on this.
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Written and checked by the OneCraft team. Last checked .