How to Blur Part of an Image Online: Hide Faces, Plates and Private Details Before You Share
A sports day photo full of other people’s children. A car listing with a readable number plate. A group chat screenshot showing everyone’s name. Each needs the same job before it goes anywhere: you want to blur part of an image online and be sure the hidden part stays hidden. This guide shows how to blur image areas, pixelate image regions or cover them with a solid box, which of those effects to pick for a blur face job versus a card number, and what to do about the details a censor image step cannot reach.
1. Blur, Pixelate or Censor an Image: What It Is For
Blurring a whole photo is a style choice. Blurring one part of it is a privacy choice: you want to share the picture without also sharing a face, a plate or a number that was never yours to publish. So this tool works on regions. You pick the rectangles to hide and everything else stays sharp.
It offers four effects, and they are not interchangeable:
- Blur — a soft smear that keeps the colour of the area and looks natural over a face.
- Pixelate — the familiar mosaic of square blocks, obviously “censored”.
- Black box — a solid black rectangle. Nothing of the original shows through.
- White box — a solid white rectangle, the cleanest choice for a scanned form or a light screenshot.
Use it whenever a picture is about to leave your hands: a post, a listing, a support ticket, a report. If you only need to cut away an edge rather than hide something inside the frame, the image cropper is the simpler fix.
2. How to Blur Part of a Picture in Four Steps
Here is how to blur part of a picture with the tool above. The same steps answer how to pixelate part of an image and how to black out text in an image; only the effect you choose in step three changes.
- Add the image. Drop it on the panel, click to choose it, or paste a screenshot from your clipboard.
- Drag to draw regions. Drag a rectangle over each thing to hide, as many as you like. The dashed blue outline shows only in the preview, not in the saved file. Click inside a region to remove it, or press Clear regions to start over.
- Choose the effect and strength. Pick Blur, Pixelate, Black box or White box. The Strength slider runs from 2 to 60: softness for Blur, block size for Pixelate, no effect on the solid boxes. Regions update as you move it.
- Pick a format and download. Choose JPG, PNG or WebP and press Download. The file is saved with -censored added to its name, beside your untouched original.
A simple format rule: JPG for photos, PNG for screenshots, where crisp text matters. PNG is also the answer for a pixelate face PNG online job for a slide. Need a smaller file afterwards? The image compressor handles that as a separate step.
3. Blur Face or Black Box? Match the Effect to the Risk
This is the decision most guides skip. People ask can blurred text be unblurred because they have seen it happen. The honest answer: a light blur or a fine mosaic over text can leave enough shape for a determined reader to guess the words, especially a predictable format like a card number.
Faces and scenery
Blur looks the most natural here. Raise the strength until someone who knows the person could not recognise them, and draw the rectangle a little larger than the head.
Text, numbers and plates
Use Black box or White box, which carry nothing of what was underneath. If you prefer a mosaic, use Pixelate at high strength so each block covers several characters.
So, is pixelating a license plate safe? With small blocks, not reliably, because a plate has a known layout. With large blocks, or better a black box, the plate is gone. Whichever effect you use, the pixels in each region are permanently replaced in the download; nobody receiving it can switch the effect off.
4. Faces, Plates, Cards, Addresses and Chat Screenshots
The same four steps cover very different jobs, each with its own best setting.
- Blur faces of children in photos before posting: draw a region over each face you have no permission to share and use Blur at a generous strength. This is how to blur a face in a photo without making it look vandalised. The photo is never stored on our servers and nothing is retained after you download it.
- Blur license plate for car sale listing: one rectangle per plate, Black box or strong Pixelate. The same works for any blur license plate online job on a street or dashcam still.
- Blur credit card number in photo: receipts and unboxing shots catch card digits more often than people notice. Cover number, expiry and name with a Black box.
- Blur address on package photo: box the whole shipping label, not just the street line.
- Censor names in chat screenshot: this is how to hide personal information in a screenshot: paste it in, box every name, avatar and number, and export as PNG.
- Blur part of an image on iPhone: open this page in Safari, add the photo from your library, and draw regions with a finger. If a HEIC photo will not open, convert it with HEIC to JPG first.
5. Hidden Is Not the Same as Private
When you set out to anonymize photo online, the visible part is only half the job. Phone photos usually carry EXIF metadata, which can include the device and the GPS location of the shot. A blurred face in a file that records a home address has not protected much. De-identification guidance such as NIST IR 8053 makes the same point: identifying information hides in more places than the obvious one.
This tool is for what people can see. For what the file itself records, use the EXIF remover, which strips location and camera data and shows what was removed. Run both before posting anything sensitive.
Check the whole frame before you download. The tool hides exactly what you mark. Reflections, name badges and text on a screen in the background are what most often slip through.
6. What the Tool Does Not Do, and Where to Go Instead
A tool you trust with private photos should be clear about its edges.
- No automatic face or plate detection. You draw every region, so nothing is guessed and nothing you wanted to keep is blurred by mistake. The flip side is that a face you did not mark stays visible, so scan crowds and backgrounds carefully. No tool on this site detects faces or plates automatically.
- Rectangles only, one effect for all. There is no brush, circle or lasso, and every region shares one effect and strength. For a mix, download one pass as PNG, load that copy and add the next effect, then pick your final format on the last pass. Saving the in-between copy as PNG avoids compressing a photo twice.
- One still image at a time. No batch mode and no video blur.
- Large images are capped. A picture whose longest side is over 3000 px is scaled down to 3000 px. For exact dimensions afterwards, use the image resizer or the image enlarger.
- No portrait-style background blur. The background remover removes a background rather than blurring it.
- Not for PDFs. This tool can redact image online files, but for text inside a document use PDF redact.
- No unblurring. The effect is deliberately permanent, and no tool here recovers hidden detail.
7. Why Cortexis Is the Best Free Image Censor Tool
Whether you searched to blur face in photo online free or to pixelate image online, many pages end in a full editor that wants an account or stamps a logo on the export. Here is what this image censor tool offers instead.
A blur tool without sign up
No account and no email. Open the page, mark the image, download it.
Blur image without watermark
The downloaded file carries your picture and the regions you drew, with no logo or stamp added.
Four effects, one decision
Soft blur for a face, a black box for a card number, and a white box to white out part of image online forms and scans.
Your photos stay private
Images are never stored on our servers and nothing is retained once you are done.
Nothing is used for training
Your photos are never used to train anything. A picture of your child or your car stays yours.
You stay in control
Every region is drawn by hand, the effect is permanent in the download, and your original file is left untouched.
It is one of a wider set of free image and document tools built on the same terms. To add your own mark instead, the image watermark tool is the companion to this page.
8. Frequently Asked Questions (FAQ)
How do I blur part of an image online for free?
Add the image to the tool above, drag a rectangle over each area to hide, choose an effect and press Download. The file is saved with -censored in its name, with no account, watermark or charge.
Can I blur a face without it looking odd?
Yes. Use Blur, draw the rectangle slightly larger than the head, and raise the strength until the person is unrecognisable. Blur keeps the colours of the area, so it sits more naturally than a black box.
Can blurred text be unblurred?
Weak blur or fine pixelation over text can sometimes be guessed, especially numbers in a known format. For text, card numbers and plates, use Black box or White box, which leave nothing behind. Every effect permanently replaces the hidden pixels in the download.
Does the tool detect faces or license plates automatically?
No. You draw every region by hand, so nothing is blurred by guesswork, but anything you do not mark stays visible. Check the whole photo for faces, plates and text before downloading.
Is my photo stored anywhere?
No. Your images are never stored on our servers, nothing is retained, and nothing is used for training. For extra privacy, remove location data with the EXIF remover before sharing.
Can I use different effects on different regions?
Not in one pass; the effect and strength apply to every region. To mix them, download with the first effect as PNG, load that copy, and add the rest with the second.
Why is my downloaded image smaller than the original?
Images whose longest side is over 3000 px are scaled down to 3000 px. Smaller images keep their size. For exact dimensions, use the image resizer.
Can I blur faces in a video or several photos at once?
No. The tool edits one still image at a time. For several photos, repeat the steps for each; no tool on this site currently blurs video.
Censored and ready to share? Strip location data with the EXIF remover, convert the result with the image converter, open an AVIF photo first with AVIF to JPG, or turn a set of censored pictures into one document with image to PDF. To learn retouching in a full editor, our free graphic design course covers selections and masks from the ground up.