Image Sharpen Tool
Crisp up soft or slightly blurry photos in your browser.
How to use
- 1 Drop an image onto the box, or click to choose a file.
- 2 Drag the strength slider to taste.
- 3 Watch the live preview update from the original pixels.
- 4 Click Download PNG to save the sharpened image.
About Image Sharpen Tool
The Image Sharpen Tool brings back the crisp edges that get lost when a photo is resized, scanned, shot slightly out of focus, or saved through one too many compression passes.
Drop in a JPEG, PNG, WebP or GIF and it is decoded, sharpened and previewed entirely on your own device.
Under the hood it applies a classic 3x3 high-pass (unsharp-mask) convolution.
Each pixel is compared with its four neighbours, and the difference is amplified by a strength you control with a single slider, so detail and texture pop while flat areas of even colour stay clean.
Because the kernel is balanced — the centre weight grows exactly as much as the surrounding negative weights — overall brightness is preserved, and a perfectly smooth region comes out unchanged rather than tinted or banded.
Nudging the slider redraws the result instantly from the original pixels, so you never sharpen an already-sharpened image and pile up halos; you simply find the setting that looks best.
Everything happens locally with the Canvas API, so your picture is never uploaded, stored or logged, and the tool keeps working offline once the page has loaded.
When the detail looks right, download a lossless PNG.
FAQ
Is my image uploaded anywhere?
No. Sharpening is done with the Canvas API inside your browser, so the file never leaves your device.
Why does too much sharpening look bad?
High strengths exaggerate noise and create bright halos around edges. Start low and raise the slider until detail is crisp but artifacts have not appeared.
Can sharpening fix a badly blurred photo?
It recovers fine detail and edge contrast that is still present but faint. It cannot invent detail that motion or heavy defocus has truly destroyed.