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Free Browser Tool

Blur Image — Add Gaussian Blur Effect Online

Apply a smooth Gaussian blur to any JPG, PNG, or WebP image. Drag the slider to control intensity. Preview updates live. Download instantly. Your image never leaves your device.

No Upload · Private
Adjustable Blur
Live Preview
Free Forever
Blur Image Tool

Drop your image here

or tap to browse from your device

JPG · PNG · WebP · GIF
8 px
No blur (0)Heavy blur (50)

Frequently Asked Questions

This tool applies a Gaussian blur using the CSS filter: blur() property via the HTML Canvas API. Gaussian blur is the industry-standard algorithm used in Photoshop, GIMP, and Lightroom. It produces smooth, natural-looking softness by blending each pixel with its neighbours using a bell-curve weighting. The radius slider controls the strength — larger values blend more pixels together.
1–5 px — subtle skin softening or soft glow.
5–15 px — depth-of-field style background separation.
15–30 px — heavy privacy blur for faces, plates, or text.
30–50 px — extreme artistic or dreamy effect. The live preview updates as you drag so you can find the right level instantly.
This tool applies blur uniformly to the entire image. For selective region blurring (e.g. just a face or number plate), you'll need a more advanced editor like Photoshop, GIMP, or the browser-based Photopea.
Yes — blurring removes high-frequency detail which compresses more efficiently. A heavily blurred JPG or WebP can be 20–40% smaller than the original because smooth gradients encode much more compactly than fine texture.
No. The blur is rendered onto an HTML Canvas in your browser. Your original file on disk is never touched. You can adjust the radius and re-apply as many times as you like — only the file you download contains the effect.

About One Doc Studio

One Doc provides Forever Free browser-based tools. Nothing is ever uploaded. Your files never leave your device.

Free Image Blur Tool Online — Apply Gaussian Blur to Any Photo Instantly

Blurring images serves many purposes in photography, design, and content creation. Background blur creates a pleasing depth-of-field effect that draws focus to the foreground subject — a technique photographers call bokeh. Privacy blur obscures faces, licence plates, addresses, and identification numbers before sharing images publicly. Artistic blur gives photos a dreamy, soft-focus aesthetic used extensively in fashion and editorial photography.

The Image Blur tool on OneDocPDF applies a Gaussian blur effect directly in your browser using the Canvas filter API, with a radius slider from 0 to 50 pixels and a live preview that updates as you drag. Gaussian blur is the standard algorithm used across all major photo editors including Adobe Photoshop, Lightroom, and GIMP. It works by replacing each pixel with a weighted average of its neighbours — producing smooth, natural-looking results without the ring artefacts that simpler blur algorithms can introduce.

For privacy and redaction, a radius of 15–25 px is typically sufficient to make faces and text unrecognisable while clearly indicating intentional obscuring. For regulated industries, consider whether blur alone meets your redaction requirements or whether solid black coverage is needed.

For related tools see our Brightness & Contrast tool, our Grayscale converter, our Image Watermarker, and all free image tools on OneDocPDF.