Image Blur Tool

What the Image Blur Tool Does

This applies a Gaussian blur to an image — the smooth, soft-focus blur used for frosted backgrounds and out-of-focus looks. A slider sets the blur radius in pixels, from 0 (unchanged) up to 30 (heavy).

The blur covers the entire image; you cannot blur just a face or a single region with this tool. The preview updates as you drag, and the output is a lossless PNG at the original size.

How It Works

Drop or pick an image. It is drawn onto a canvas in your browser.

Drag the blur slider. The tool sets the canvas filter to blur at your chosen pixel radius and redraws, so the preview is the real result.

Download saves a lossless PNG at the original dimensions. The canvas re-encode also strips EXIF and GPS metadata.

Processing pipeline

1. Decode locally. Your image is drawn onto a canvas in the browser — never uploaded.
2. Set the blur radius. The slider value, 0 to 30 pixels, sets the strength of the Gaussian blur.
3. Apply the Gaussian filter. The browser blurs the whole image in one pass and redraws it.
4. Export the PNG. The blurred canvas is saved as a lossless PNG with your original base name.

The filter applied

The pixel value sets the standard deviation of the Gaussian — the bigger it is, the wider each pixel smears into its neighbours. A value of 0 leaves the image unchanged.

Privacy

Your image is blurred entirely in your browser and never uploaded — there is no server.

The canvas re-encode strips all EXIF and GPS metadata, so the blurred PNG carries no camera or location tags.

A blur is a visual softening, not secure redaction — read the limitations below before using it to hide sensitive details.

No account, no stored copy; everything is gone when you close the tab.

Technical Details

Standards & references

• Gaussian blur — A weighted average of nearby pixels using a Gaussian (bell-curve) distribution; the pixel radius sets the standard deviation.
• CSS blur() filter — The standard blur() filter function; the value is a length in pixels and cannot be negative.

Accuracy & Limitations

A blur is not secure redaction. Blurred and pixelated faces or text can often be reconstructed — AI and forensic deblurring tools exist, and blurred text is especially exposed because every instance of a letter blurs the same way, which lets software brute-force it back. To truly hide something, cover it with a solid block or delete it; do not rely on blur.

The blur covers the whole image. There is no region or brush mode, so you cannot blur only a face or a number plate with this tool.

Blurring permanently discards fine detail in the saved PNG, so to you it is irreversible — but 'softened past your reading' is not the same as 'unrecoverable' by a determined tool.

Output is a lossless PNG at the original dimensions. The blur adds no compression artefacts of its own, though a heavy blur on a large image takes a moment to render.

Real-World Use Cases

When to use it — and when not to

To hide sensitive details, cover them with a solid box in an editor or crop them out — never rely on blur or pixelation. To blur only part of an image, use an editor with a selection or brush.

Frequently Asked Questions

References

• blur() CSS function (MDN)
• Blur and Pixelation: The False Security of Visual Censorship (State of Surveillance)
• Researcher 'reverses' redaction, extracts words from pixelated image (BleepingComputer)
• CanvasRenderingContext2D: filter (MDN)

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