PDkef
PDF redaction guide
On-device
Choose the result you want

Blur, Blackout, Whiteout or Delete PDF Text?

Four tools, four useful results. Remove an element, clear a field for replacement text, show that information was withheld, or soften part of a page. This visual guide shows what each one does to the same filled-in form, then explains what flattening changes when you download.

Start with the outcome

What do you want the finished PDF to look like?

The same editor gives you four different ways to change a PDF page.
ToolChoose it when you want toA practical exampleWhat happens on Download
DeleteRemove an existing text or image elementTake out a wrong answer or a watermarkThe selected element is deleted from the page; the rest stays selectable
WhiteoutCover an area with a clean, page-colored boxHide an old form value and type a replacement over the cleared fieldThe marked page is flattened into one image
BlackoutCover an area with a clear solid redactionBlack out a name, reference number, address, or part of a scanThe marked page is flattened into one image
BlurSoften visual detail while leaving context visibleBlur a phone number, face, signature or screenshot detailThe marked page is flattened into one image

There is no single “best” option because these are different jobs. Delete changes the page content. Whiteout, Blackout and Blur change how an area looks. The Redact tool puts all four in one place so you can choose per item, and even combine them on one document.

Use case: replace prefilled data

Delete the old value, then enter the new one

A form went out with the wrong employer on it. Choose Delete and click the highlighted value. The selected element is removed from the PDF page. The field, its label and all other page text stay in place and remain selectable.

A filled-in form with Green Valley Ltd as the employer, wiping to the same form with Blue Harbor LtdBeforeAfter
Delete took out the wrong employer, then Sign & Fill PDF put in the right one. Nothing else on the page changed, and it is all still searchable text.
  1. 1Choose Delete. The editor highlights the text and image elements it can remove. Click the complete element you want gone.
  2. 2Download the edited PDF. The selected value is deleted from that page. Delete-only pages keep the rest of their text selectable and searchable.
  3. 3Open the result in Sign & Fill PDF. Add the new value in the cleared space, position it, and download the completed form.

This also works for a watermark an app stamped on your file, an outdated heading, an old price, a duplicated line, a logo, or a picture you no longer want on the page. When a link sits over the watermark, Delete takes the link too.

The bottom of a signed form with a Made with TrialScan Free watermark, wiping to the same form without itBeforeAfter
One click on the watermark removes it and the link under it. Searching the saved file for its name finds nothing.

A scan is usually one large image rather than separate words, so use Whiteout when you only need to clear one part of a scanned form.

Use case: clear and write over

Whiteout gives you a clean surface for replacement text

Whiteout is the visual alternative. Draw a box over the old answer, pick its color to match the page or field behind it (it starts white), download the flattened page, then add a new answer with Sign & Fill PDF. It is especially useful when the old value is part of a scan and cannot be selected as its own text element.

A filled-in street address field, wiping to the same field with the text gone and its grey-green color keptBeforeAfter
Whiteout covers the street address in the field's own color. The color is picked from the box's color control, so the patch is invisible against the field. Unlike Delete, it becomes part of a flattened page image when you download.

Choose between them by result: Delete when you want the element gone and the rest of the PDF page preserved as searchable content. Whiteout when you want a clean visual patch, including on scanned or image-based pages.

Use case: make the omission visible

Blackout clearly shows that content was removed from view

Blackout is intentionally visible. Use it when the reader should understand that a name, number, address, paragraph, or image region was withheld. Because you draw over an area, it works on normal PDFs and scanned pages alike.

A filled-in ID number, wiping to the same form with the ID number under a solid black boxBeforeAfter
Blackout creates an unmistakable solid cover. Anyone reading the form can see an ID number was there, and none of its digits are left in the saved file.
  1. 1Choose Blackout and drag across the full area you want covered.
  2. 2Repeat wherever needed. Pick Blackout again, or keep the tool on for several areas.
  3. 3Download. Every page carrying a Blackout, Whiteout or Blur mark is flattened automatically.
Use case: soften visual detail

Blur keeps the shape and context of an area

Blur is useful when a hard rectangle would dominate the page. Soften a phone number on a form you share as an example, a face in a photo, a handwritten signature, or a screenshot detail, anything that should stay visibly there without being readable.

A filled-in phone number, wiping to the same form with the number blurred at the light settingBeforeAfter
Blur on its light setting: you can see a number was there, not read it. The box stays adjustable in the editor and is baked into the page on Download.

To blur text in a PDF, choose Blur and drag a box over the words. There is no text-selection step, so on a phone zoom in first to place the box precisely. After Download the page is one flattened image and the words are gone as text, but blurred pixels can still hint at a short or predictable value.

Blur is a design choice rather than a substitute for Blackout. Choose the result that fits your document: softened context with Blur, an explicit solid cover with Blackout, a clean patch with Whiteout, or actual element removal with Delete.

The irreversible export choice

Flattening makes the marked page one-way

Diagram showing an editable blackout box becoming part of one flattened page image during download
No separate Flatten button is required. Download automatically flattens pages that contain Blur, Blackout or Whiteout marks.

Before Download, the cover or blur is an editable object: move it, resize it, recolor a Whiteout, or undo it. During Download, PDkef renders the page and its marks together into one page image. In that exported PDF the mask is no longer a separate object, so the action is intentionally one-way.

Flattening changes the whole marked page, not only the box.
After DownloadPage with Delete onlyPage with Whiteout, Blackout or Blur
Selected changeThe selected element is deletedThe visual mark is baked into the page image
Other textStays selectable and searchableBecomes pixels and is no longer searchable or selectable
Can the edit be moved later?The element is already gone from the exported pageNo; the mark is part of the flattened page image
Best fitRemoving or replacing page elementsCreating a final, fixed visual result

Keep the original when you may need another version. Your browser draft remains separate from the downloaded result, so you can return to the editor, adjust the marks, and export a new copy without changing the one you already downloaded.

Free, private, open source

Try every option without uploading the PDF

The tool is free, has no account or watermark, and processes the PDF in your browser. The code is open source under the MIT license. You can check how local processing works or install PDkef for offline use after the required assets have loaded.

Ready to choose by result? Open Blur & Redact PDF, try the tools on a sample, and download a new copy when it looks the way you want.

Open the free PDF redaction tool
Got questions?

Frequently asked questions

What does Delete do in a PDF?

Delete removes the selected text or image element from the PDF page. The surrounding page content remains in place, selectable and searchable. Use it to remove or replace prefilled form data, outdated text, a logo, a picture, or another element you no longer want.

Should I use Delete or Whiteout to replace a form value?

Use Delete when the old value is highlighted as its own removable element and you want it gone from the page. Use Whiteout when you want to cover the area with a clean patch, especially on a scan. Download the result, then use Sign & Fill PDF to enter the replacement value.

What is the difference between Blackout and Blur?

Blackout creates a solid, unmistakable cover that shows information was withheld. Blur softens an area while keeping its shape and surrounding visual context. Both are adjustable in the editor and become part of a flattened page image when downloaded.

What does flattening a PDF page do?

Flattening renders a page and its Whiteout, Blackout or Blur marks into one page image. The marks cannot be moved in the downloaded copy, and the page text is no longer selectable or searchable. PDkef does this automatically when you download a page carrying those marks. The word has a gentler meaning in Sign, where a filled-in form is flattened on download: the answers become part of the page and the text stays selectable.

Does Delete flatten the PDF page?

No. A page with Delete edits only is not flattened. The selected element is removed and the rest of the page remains normal selectable PDF content. If the same page also has Whiteout, Blackout or Blur, that page is flattened on Download.

Can I combine Delete, Whiteout, Blackout and Blur in one PDF?

Yes. Choose the result you want for each part of the document. You might delete an old form value, white out another field, black out a reference, and blur a photo detail before downloading one finished PDF.

Same suite

More PDF tools

Every one of these runs on your device, free, with nothing uploaded.

Also: Extract PDF Pages · Rotate PDF · Remove PDF Pages · Add Page Numbers to PDF