Calculator
What the Crop PDF does
Crop PDF: trims the margins you enter (in millimetres) off every selected page by setting the crop box, which every viewer honours, or the media box for a permanent cut. Everything runs in your browser and the file is never uploaded.
Drop in a file and the Crop PDF handles it locally. Processing is local, so speed depends on your machine rather than someone else’s server load.
Uploading a document to an unknown server is exactly what you should avoid with anything private. That is usually what brings people preparing a file to send here.
No upload means no copy of your document sitting on somebody else’s server.
Below the tool you will find the field reference, the method, and an example computed from the values it opens with.
What do the Crop PDF fields mean?
The Crop PDF uses 7 inputs. Because the form arrives filled, the first useful result costs you zero typing.
| Field | What to enter | Default |
|---|---|---|
| PDF File | stays on your device | none |
| Top | measured in mm; accepts 0 to 300 | 10 |
| Right | measured in mm; accepts 0 to 300 | 10 |
| Bottom | measured in mm; accepts 0 to 300 | 10 |
| Left | measured in mm; accepts 0 to 300 | 10 |
| Crop type | choose from Crop box (reversible in a PDF editor) or Media box (permanent) | Crop box (reversible in a PDF editor) |
| Pages (all, or e.g. 1-3,5) | required | all |
How does the Crop PDF work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same result.
Validation runs before the calculation, which is why a mistyped value shows an error rather than a plausible-looking result.
What a typical run looks like
You provide: PDF File, Top, Right, Bottom, Left, Crop type and Pages (all, or e.g. 1-3,5)
What happens: the file is read into memory by your browser, processed locally, and offered back as a download. It is never uploaded.
You get back: the finished file to download, with a line in the panel saying what was done.
Because the work is local, speed depends on your device rather than our servers, and large files are limited only by available memory.
How to use it
- Choose your file under PDF File, or drag it onto the drop area.
- Enter Top in mm (0 to 300).
- Set Right in mm (0 to 300).
- Put Bottom in mm (0 to 300).
- Key in Left in mm (0 to 300).
- Pick a value for Crop type: the options are Crop box (reversible in a PDF editor) or Media box (permanent).
- Type Pages (all, or e.g. 1-3,5).
- Press Crop.
- Look at Status, Pages cropped and New page size in the output panel.
- Use Copy Link if you want the same setup again later, or Print for a paper copy.
What this tool does not do
- Encrypted or password-protected files must be unlocked before they can be processed.
- Very large documents are limited by your device memory, not by a server quota.
- Comparisons across tools can differ where each uses a slightly different definition.
- Nothing here can catch a correct number entered in the wrong field.
- Because everything runs locally, processing speed depends on your device rather than our servers.
Frequently asked questions
Enter Top in mm, Right in mm, Bottom in mm and Left in mm. Both the inputs and the result are explicitly labelled, so mixed units cannot slip through unnoticed.
Top accepts 0 to 300 mm. Anything beyond those bounds is flagged rather than approximated.
No upload takes place. The file is handled entirely in the browser and discarded when you close the tab.
Free for any use, personal or commercial.
It follows the standard definition for this operation, so the result matches what a reference implementation would give.