chevron_right

Image Sharpen Tool

Sharpen blurry photos in your browser with a precise convolution-based sharpening filter. Adjustable strength, fully private.

upload_file

Click to browse or drag & drop files here

Select an image

Accepted: image/*

Similar Tools

Blur Image

Apply a smooth Gaussian blur to any image directly in your browser. Adjustable radius, live preview, fully private.

Invert Image Colors

Invert the colors of any image instantly in your browser. Adjustable intensity, optional alpha inversion, fully private.

Sepia Filter

Apply a classic sepia tone to images instantly in your browser. Adjustable strength and warmth, fully private, no upload required.

Grayscale Image Converter

Convert any image to grayscale instantly in your browser. Choose between luminance, average, and lightness algorithms with adjustable intensity.

Audio Compressor

Apply dynamics compression to audio with adjustable threshold, knee, ratio, attack and release controls.

GIF to MP4

GIF to MP4 helps you turn animated GIFs into video files directly in your browser. Use it for fast, private media cleanup, publishing, lessons, demos, and everyday video or audio editing.

GIF Reverser

Reverse the frame order of any animated GIF directly in your browser. Preserves per-frame delays, fully private, no upload required.

apps

More Tools

Browse our full collection of free online tools.

Image Sharpen Tool

Recover crispness and detail in slightly soft photos using a precise 3×3 convolution sharpening filter. The tool runs entirely in your browser using the Canvas API and applies a classic unsharp-mask style kernel.

How it works

The sharpen filter amplifies the difference between each pixel and its neighbors. With a strength of 1.0 it uses the classic sharpen kernel [0,-1,0; -1,5,-1; 0,-1,0]. Higher strengths progressively widen the edge response, producing more aggressive enhancement.

Use cases

Crisp up slightly soft phone photos
Recover detail after resizing or compression
Enhance product photography for e-commerce listings
Improve readability of scanned documents and screenshots
Bring out texture in macro and landscape shots
Final pass before publishing to social media

Tips

Values 0.3–0.8 give subtle, natural-looking sharpening for most photos. Values 1.0–2.0 are useful for screenshots and documents. Beyond 2.5 the filter starts to create visible halos and noise — useful only for stylized looks.

All processing happens locally — your originals never leave your device. Output is a high-quality PNG.