Redaction

Image blur and pixelate

Details

How to use Image blur and pixelate

What the tool does, how to run it, and what to expect from the result.

How to blur or pixelate part of an image

To redact an image, drop it into the tool, drag a rectangle over the area you want to hide, and choose blur, pixelate, or a solid fill. Repeat for as many regions as you need, then export the finished image. The rest of the picture stays exactly as it was.

The whole workflow runs in your browser, so the image is never uploaded to a server. That means a sensitive screenshot or document can be redacted and exported without ever leaving your device, and there is no upload queue or wait.

  • Drop in the image
  • Drag a rectangle over the area to hide
  • Choose blur, pixelate, or solid fill
  • Repeat as needed, then export

Why redact before an image leaves your device

A lot of image sharing risk is not about aesthetics, it is about visible details that should not travel further: faces in the background, phone numbers, order details, map coordinates, chat names, or interface elements that were never meant to be public.

A browser-first redaction tool solves that cleanly. It lets you hide exactly the part that matters, keep the rest of the image intact, and export with confidence, all without sending the file to a server first. That privacy is the whole point when the content is sensitive.

  • Redacting screenshots before support tickets, docs, or social sharing
  • Hiding faces or license plates in everyday photos
  • Masking names, addresses, numbers, and account details
  • Cleaning up product, dashboard, or admin screenshots before publishing

Blur, pixelate, or fill: which to use

Blur is best when you want to soften a detail without making the edit look harsh, keeping the image natural while still obscuring what matters. Pixelation is better when you want the redaction to read clearly as intentional, with a visible mosaic over the hidden area.

A solid fill is the strongest option. When a screenshot or document area must be completely unreadable, a flat block leaves no recoverable detail, which makes it the safest choice for highly sensitive information like account numbers or credentials.

Tips

Getting a better result out of Image blur and pixelate

Specific settings and thresholds, not general advice.

  • Blurring or pixelating text is weaker than it looks. If the hidden text has a small set of plausible values, someone can render each candidate, apply the same blur radius or block size, and compare against your image until it matches. For an account number, a token, an address, or a name, use the solid fill, which replaces the pixels with a flat color and leaves nothing behind to compare against.
  • The pixel block size runs from 4px to 48px and defaults to 18px. To be a real mask, the blocks must be bigger than the characters underneath. Blocks smaller than the text's cap height preserve enough of the letter shapes that the word can still be read at a distance.
  • The blur radius runs from 4px to 40px and is measured in the image's own pixels. On a 4000px wide photo, an 18px radius is a gentle smudge. On a 900px one it is a heavy blur. Scale it with the image, not with what looks strong on screen.
  • The default solid fill color is a dark charcoal rather than pure black, which reads as a deliberate redaction mark on a screenshot rather than a rendering glitch. You can change it to any color, including the exact background of the app you captured.
  • Every action is stacked and then flattened into one canvas on export, so the downloaded PNG, JPG, or WebP contains only the final pixels. There is no layer to peel back and no original hiding inside the file.
Limits

What Image blur and pixelate does not do

The honest boundary, so you do not lose time finding it yourself.

  • Rectangular regions only. There is no brush, ellipse, or lasso.
  • It does not find faces or sensitive text automatically. Every region is drawn by hand.
  • One image per session, with no batch processing.
  • There is no crop. Use the screenshot redactor if you also need to cut away outer context.
Reference

Terms used on this page

Short, plain-language definitions for the formats and settings above.

At a glance

Who Image blur and pixelate is for

A quick way to understand who this helps, what it solves, and where it connects next.

Best fit

People hiding faces, numbers, names, addresses, interface details, and other sensitive visual information

Ideal for

Quick screenshot cleanup, face masking, and simple redaction before upload or sharing

FAQ

Common questions

Short answers for the questions people usually have before trying a utility like this.

Is this image redaction tool free?

Yes. Blurring, pixelating, and filling areas of an image is completely free with no sign-up or limits.

Does it upload my image to a server?

No. The editing runs entirely in your browser so the image stays on your device while you redact it. Nothing is uploaded.

When should I blur instead of pixelate?

Blur is better for softening a detail without a harsh look, while pixelation reads more clearly as an intentional redaction. For fully unreadable areas, use solid fill.

Why include a solid fill option?

Some screenshots and documents need a stronger mask than blur or pixelation. A flat fill is the clearest choice when the hidden area must be completely unreadable.

Does it work on mobile?

Yes. The tool runs in any modern browser, including mobile, so you can redact an image directly on your phone before sharing it.

Blur or pixelate: which is more secure?

Neither is secure for text. Both are reversible in principle when the underlying content comes from a small set of possibilities, which is exactly the case for numbers, names, and rendered UI strings. For a face or a photographic background, both are fine. For anything you actually need hidden, use the solid fill.

How big should the pixel blocks be?

Larger than the thing you are hiding. If the text is 14 pixels tall, blocks of 8 pixels will still show you the shape of each character. Push the block size until the region is unreadable when you zoom out and squint, which is a surprisingly good proxy for what a reconstruction attack can recover.

Can I apply several effects to the same image?

Yes. Each rectangle you draw is added to a stack, and you can mix blur, pixelate, and solid fill across one image. The stack is applied in order onto a fresh copy of the original, so you can revert the last action or clear everything without reloading the file.

Does the exported file still contain the original pixels?

No. Every action is rendered onto a flat canvas and the file is encoded from that canvas alone, so what you download contains only the modified pixels. There is no hidden layer, no undo history in the file, and re-encoding also drops the source image's metadata.

Is the image uploaded to apply the effect?

No. Decoding, blurring, pixelating, filling, and encoding all run in the page on your own device, which is why this is safe for a photo of a person or a screenshot of an internal tool. The only network call is a credit counter carrying the tool name.

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