How do I permanently hide information in a PDF?
Draw a rectangle over what must disappear. The area is erased from the content, not merely covered: the text underneath no longer exists in the file.
Redact PDF
Truly remove a passage, not just hide it on screen.
A black box drawn over text does not delete it: it stays inside the file, and a plain copy-paste brings it back. Here, redacted pages are redrawn and the hidden text is gone for good. And since everything runs on your device, the confidential document is never sent anywhere.
This tool runs entirely in your browser. Your file is not sent anywhere.
Drop your fileor click to browsePDF files
Why a black box hides nothing
A PDF is not an image: it is a sequence of drawing instructions, stacked in the order they were written. Dropping a black rectangle over a passage adds one instruction at the end of the stack. The ones before it do not move. The covered text is still there, intact, in the page stream.
Recovering it takes no particular skill. Selecting the passage with the mouse and pasting it elsewhere usually does the job: the text copies out from under the rectangle, because it was never removed. A keyword search finds it. A plain-text export returns all of it.
It is the most ordinary document leak there is, and it has cost governments, newsrooms and law firms dearly — all of them convinced they had hidden a name, an amount or an address.
What this tool does instead
The pages you redact are redrawn in full, mask included, then placed back into the document as an image. The text is no longer covered: it no longer exists in the file. Only pixels remain.
The cost is real and worth knowing before you start: those pages stop being selectable and searchable, and the file grows. Pages where you redacted nothing are copied across untouched and keep their text — the document does not turn into a stack of images from end to end.
The original document's metadata is not carried over. Author, title and creating software often say more about where a file came from than its contents do, and letting them through would empty the work you just did of its meaning.
Check before you send
Do not take our word for it: redaction is exactly the kind of thing you can verify yourself, and three gestures are enough.
- Open the redacted document and try to select the hidden passage with the mouse. Nothing should select.
- Run a search for a word you masked. It should find nothing.
- Save the document as plain text, then open the result. The passage should not appear.
Cropping, covering, redacting: three different gestures
Cropping moves the visible frame of the page. Whatever falls outside stays in the file and comes back the moment the crop is undone: it is a layout change, not a deletion.
Adding an annotation, an opaque highlight or a filled shape is the same misunderstanding as the black box. The added layer can be removed, and what it covered returns.
Only redaction deletes. It is also the only one of the three you cannot undo: work on a copy, and keep the original if you may need it later.
Common questions
How is this different from drawing a black box on top?
Entirely. A drawn box hides on screen but leaves the text in the file — it can be copied, searched and recovered. It is the most common document leak there is.
Are my files uploaded to the internet?
No. This tool runs entirely in your browser: the document is opened on your device, processed there, and never sent anywhere. You can even go offline once the page has loaded.
Is it free, and do I need an account?
Free and unlimited, with no account and no sign-up. This tool costs us nothing because it runs on your machine, so we have no reason to ration it.