Runs in your browser with pdf.js and pdf-lib
Blur PDF Online — blur or pixelate faces, names and numbers, and the text under them goes too
Drag over what to hide, or find every email, PAN or phone number at once. Choose blur or pixelate and how strong, see the exact result on every page, and download a file where the hidden text can't be copied out. The PDF never leaves your device.
- PDF files aren't uploaded to our server
- Blur or pixelate
- Find emails, PAN, Aadhaar
- Works in Safari too
Blur a PDF
Add a PDF, draw areas to blur or find them by text, pick blur or pixelate and the strength, then save. The text under the blur is removed too.
Drop your PDF here
or browse — one PDF, any number of pages
Page 1
Drag on the page to draw an area to blur.
Good to know
Blur areas
No areas yet. Drag on the page, blur a whole page, or find text below.
Area
Locked, so it can't be moved or changed by mistake. Click Unlock to change it.
Find text to blur
Searches the text of every page. Scanned pages have no text, so draw areas on those.
When you save
Effect
Your pages
Each page shows the blur exactly as it will be saved. Click a page to see it full size, or Show to work on it above.
What this tool does
Blur and redaction solve different problems
Blur keeps the page looking natural while hiding the details. Redaction replaces them with a solid box. Both remove the text underneath here; they differ in how much of the picture is left.
What you can do
- Blur or pixelate any area: a face in a photo, a signature, an account number, a whole page.
- Find emails, Indian mobile numbers, PAN, Aadhaar, card numbers or your own words, and blur every one.
- Put one area on several pages, for a header, footer or logo, and lock areas once they're right.
- See the exact saved result on every page before you download, in any browser, Safari included.
- Remove the text under each blurred area from the file, plus document info, comments and attachments if you choose.
When to use Redact PDF instead
- A light blur can leave large text readable, and a short known word can sometimes be guessed from its blurred shape.
- For ID numbers, legal, medical or financial details that must never come back, use Redact PDF: a solid box leaves nothing to guess from.
- Text on blurred pages can't be selected or searched any more, because those pages become pictures.
How to blur a PDF in four steps
Mark the areas, pick the effect, check every page, save once.
Add your PDF
Drop a PDF onto the upload area, or click Select PDF. The first page opens, ready for areas.
Mark the areas
- Drag on the page; drag the corner to resize.
- Or use Find text for names, emails, PAN or Aadhaar.
- Blur whole page hides everything on a page.
Pick the effect and check
Choose Blur or Pixelate and the strength. The pages show the exact result; open each one full size to make sure nothing can still be read.
For names and numbers, use strength 7 or more.
Save and download
Click Blur and save PDF. The file is checked after saving; rename it if you like and download it.
Blur or pixelate: which to choose
Strength is measured on the page, so it looks the same at every zoom and quality.
| Effect | Looks like | What to set |
|---|---|---|
| Blur | Soft and out of focus; the page still looks natural. | Faces and photos: 5 to 7. Names and numbers in normal text: 7 or more. |
| Pixelate | Large single-color squares, clearly hidden on purpose. | Text: 7 or more, so each square is wider than a letter. |
| Either, strength 1 to 4 | Lightly softened. | Only for background detail; large text may still be readable. |
| Neither | IDs and anything that must never come back: use Redact PDF. |
What blur is good for
Common jobs and the settings that fit each one.
| Document | What to hide | What to set |
|---|---|---|
| Sample report or portfolio | Client names and figures, keeping the layout. | Find text: the client's name; Blur, strength 8. |
| Photo ID inside a PDF | The face and photo. | Draw an area over the photo; Pixelate, strength 6. |
| Bank statement for a visa or loan | Other people's names and unrelated transactions. | Draw areas per row; Blur, strength 7. |
| Screenshot-style guide or manual | Emails and phone numbers in screens. | Find text: email addresses, Indian mobile numbers. |
| Letterhead or invoice template | Header and footer on every page. | One area, Put this area on: All pages. |
| Scanned document | Anything; the page is a picture already. | Draw areas by hand; Find can't read scans. |
What happens when you save
How the blur gets into the page
The steps each blurred page goes through, in order.
1. Draw the page
The page is drawn as it looks, at the quality you chose (200 dpi by default), turned and cropped as you see it.
2. Blur the pixels
Each area is blurred from the page pixels around it, so its edges blend in. This uses our own pixel code rather than the browser's canvas filter, which Safari ignores.
3. Replace the page
The picture becomes the page's only content. Its text, fonts, form fields and comments go; links outside every area keep working.
4. Clear hidden copies
The old page content and accessibility tags are dropped from the file, and document info, comments, attachments, scripts and bookmarks as you choose.
5. Check the saved file
The new file is opened again: blurred pages must have no text left, and what you searched for must not appear anywhere in it.
Pages without areas
Stay exactly as they were: text stays selectable and searchable, and links and form fields keep working.
When something doesn't look right
Identify the problem, then use the matching fix.
I can still read the text
The strength is too low for the size of the text.
Raise the strength to 7 or more, try Pixelate, or use Redact PDF.
Find text finds nothing
The page is a scan or photo, so it has no text, or the words are split oddly in the file.
Draw the areas by hand. Try a shorter part of the word, or turn off Whole words.
The edge of a word shows outside the blur
The area is a little smaller than the word in that font.
Select the area and drag its corner, or press Alt with an arrow key.
The file got bigger
Pictures of pages take more space than text.
Choose 150 dpi, or run the result through Compress PDF.
Text on a blurred page can't be selected
The whole page becomes a picture, so the hidden text can't be copied out.
Pages without areas keep their text. Blur only the pages that need it.
A password-protected PDF won't open
Encrypted PDFs can't be changed by the in-browser PDF libraries.
Remove the password with Unlock PDF, then add the unlocked copy.
Blurring with the right amount of caution
Habits that keep hidden details hidden.
Go strong on text
Strength 7 or more for names and numbers. If you can make out the shape of a word, so can someone else.
Search before you draw
Find text catches every copy of a name or number, including ones in footers and tables you might miss by eye.
Check full size
Open each page full size and zoom to 200%. Small text that looks hidden in a thumbnail may not be.
Redact IDs
Aadhaar, PAN, bank and card numbers are better removed with a solid box in Redact PDF.
Clear the document info
The title and author often name the person. Leave that option on unless you need them.
Keep the original safe
The original isn't changed. Store it separately, and share only the blurred copy.
Common questions about blurring PDFs
If something's not covered here, the troubleshooting section above likely has it.
Is blur as safe as redaction?
Not quite. Here the text under a blurred area is removed from the file either way, but the blurred picture still shows shapes, and a light blur can leave large text readable. For ID numbers and anything that must never come back, use Redact PDF, which leaves a solid box.
Is the blur part of the page, or an overlay that can be removed?
Part of the page. Every page with an area is rebuilt as a picture with the blur in its pixels, and the page's old text and graphics are dropped from the file. The saved file is checked for leftover text before you download it.
Blur or pixelate: which should I use?
Blur looks natural and suits faces, photos and backgrounds. Pixelate makes it obvious something was hidden on purpose. For text, use strength 7 or more with either.
Does it work on iPhone and Safari?
Yes. The blur is made with the tool's own pixel code instead of the browser's canvas filter, which Safari ignores, so the saved file is blurred in every browser.
Will pages I don't blur become images too?
No. Only pages with at least one area are rebuilt. The other pages keep their text, links and form fields exactly as they were.
Can it find names, emails or PAN numbers for me?
Yes. Find text looks for your own words and, if you tick them, email addresses, Indian mobile numbers, PAN, Aadhaar and card numbers, and adds an area over every match. Scanned pages have no text, so draw those areas by hand.
Is my PDF uploaded to a server?
No. The PDF is opened, blurred and checked in your browser with pdf.js and pdf-lib. It isn't sent to our server, and your original file is never changed.
Build notes
The write-up on blurring PDFs in the browser
I wrote a tutorial on building a browser-based PDF blur tool with JavaScript, pdf.js, the Canvas API and pdf-lib, with nothing uploaded to a server.
How to Build a Browser-Based PDF Blur Tool Using JavaScript
Covers rendering pages, drawing blur areas, blurring them on a canvas and writing the result back into the PDF.