裁剪 PDF
免费·无需注册·文件永不离开你的设备
How to crop a PDF in 3 steps
Cut away dead white space and edge artifacts with measurements you control, not a lasso guess.
Upload the PDF
Drop your document in the box above — it opens locally, instantly.
Set the margins
Enter how much to trim from each side in mm or inches, and confirm against the live preview.
Download the cropped file
Click Crop PDF. The trimmed document downloads right away.
Why crop PDFs with AmiPDF
Exact, repeatable trims — the same numbers across a whole document.
隐私优先
处理完全在你的浏览器内完成。不上传、不存储、不外传——绝不。
无需注册，无水印
无账号、无邮箱、无限制。输出文件与输入完全一致。
Preview before you commit
See the crop boundary over a real page before applying anything, so there are no surprises in the output.
任何设备可用
Windows、Mac、Linux、Android、iOS 上体验一致——无需安装。
When to crop PDF pages
Scans with oversized borders, slides exported with letterboxing, printouts with scanner edges — cropping tightens all of them. A trimmed page also prints larger content on the same paper.
Cropping runs entirely on your device, so private documents stay private.
Crop PDFs on any platform
AmiPDF 在你的浏览器中运行——无需安装、无需配置、无需更新。
Windows
Chrome, Edge, Firefox
macOS
Safari, Chrome
Linux
Any modern browser
iOS
Safari on iPhone, iPad
Android
Chrome, Samsung Internet
Frequently asked questions
Does cropping delete the content outside the box?
Cropping sets the visible page area — the standard, lossless way to trim PDFs. Some advanced editors can still see the underlying layer, so don't rely on cropping alone to redact secrets; use a dedicated redaction tool for that.
Can I crop just some pages?
Yes. Apply the crop to all pages or type a range like 1-5 when only a section needs trimming.
Which units can I use?
Millimeters and inches. Values are exact, so the same crop applies uniformly across pages.
Will cropping make my file smaller?
Slightly at most — the page definition shrinks, but the underlying content is preserved. Cropping is about layout, not compression.
Can I undo a crop later?
Your original file stays untouched on your device, so you can always start over from it.
Is cropping uploaded to a server?
No. The crop is computed and written locally in your browser.
相关 PDF 工具
继续——处理 PDF 所需的其他工具，全部免费、全部本地运行。