Blur Image Online Free

Client-side image blurring is a process where image pixels are manipulated to reduce detail and visual sharpness entirely inside your browser. Because we utilize HTML5 Canvas, OffscreenCanvas, and Web Worker APIs locally on your machine, your original photo is never sent to any server. This guarantees 100% privacy, data protection, and zero upload lag.

Gaussian Blur uses a bell-curve weight distribution for smooth, high-quality blurring, but can be mathematically slow for large images or strengths. Stack Blur is a highly optimized approximation of Gaussian Blur that runs in constant time regardless of the blur radius, offering smooth results and high performance. Box Blur uses a simple grid average which is fast but leaves blocky, pixelated square artifacts at higher strengths.

Our tool supports both options. You can blur the entire image at once, draw custom geometric shapes (rectangles, circles, and polygons) over specific areas like faces or text, or paint a selective mask with a soft brush for irregular shapes.

Yes, our engine handles transparent PNGs by premultiplying the RGB channels with the alpha channel before running the blur algorithm. This prevents dark, black fringe bleeding along the transparent edges of your images, producing clean, professional outputs.

Absolutely. All image loading, pixel drawing, and exporting take place locally in your browser sandbox. We do not transmit or upload your photos to any remote database, keeping your personal credentials, documents, and screenshot details safe from data breaches.