Does cropping a PDF redact it?
No. Cropping changes the visible page boundary; the content outside it usually remains inside the file and can be copied or extracted. Drawing a black box over text is the same problem. Real redaction removes the text from the file, which this tool does not do.
Why crop is not removal
A PDF page has a media box and a crop box. Changing the crop box tells a reader "show this region" — the text objects are still there, still selectable, and still returned by every extraction tool.
This is not a subtle edge case. Redaction failures in filed court documents and published reports are almost always a rectangle drawn over words that were never removed.
The test you can run yourself
Crop the page, open the result, and drag-select across the area you removed. If the text selects, it is still in the file. Then copy it into a plain text editor and look.
If it copies, anyone with a PDF library can recover it in one line of code.
What real redaction requires
The characters have to be removed from the content stream, or the page has to be replaced by an image of itself with the sensitive area genuinely absent from the pixels.
Replacing with an image is destructive and crude, but it is honest: the text is gone. It also makes the page unscannable and unsearchable, which is why it is used for one page rather than a document.
This tool does neither. It crops for layout and for tidying a scan, and it says so on the page.
What to do instead
If the goal is to stop a reader seeing a margin, crop is right. If the goal is to stop anyone recovering a name, an account number or a privileged paragraph, use a tool that removes the underlying content, and verify the output by selecting and copying.
For a passport or an identity document, treat crop as presentation only and assume everything on the page is readable.
Does this tool claim to redact?
No. The crop page and its limits both say the content outside the visible area stays in the file. That is why this guide exists.
Is a black rectangle safer than cropping?
No. A drawn rectangle is an object on top of the text, and the text underneath is fully extractable.
Can I check a file someone sent me?
Yes. Open it, select across the blacked-out area, and paste into a text editor. If characters appear, the redaction failed.
This page is general information, not advice for your document. The tools do what they say on their own pages, and every limit is printed there.