Sharpen Image

It raises the contrast at edges by comparing each pixel with its neighbours and exaggerating the difference. Edges become more defined, which the eye reads as sharper. It does not add new detail — it emphasises the detail already there.

Not really. Sharpening enhances edges that already exist, so it makes a slightly soft image crisper but cannot reconstruct detail that the lens never captured. A genuinely out-of-focus shot will only get noisier, not clear.

Start low and increase until edges look defined but natural — often somewhere around 25–40%. If you see bright or dark outlines (halos) along edges, or grain appearing in flat areas, you have gone too far.

Strong sharpening over-boosts the contrast right at an edge, leaving a light and dark fringe on either side. These halos are the classic sign of oversharpening; dial the amount back until they disappear.

It can. Because noise is made of tiny variations between pixels, sharpening amplifies it along with real detail. On noisy photos, keep the amount modest.

Yes for PNG and WebP — the alpha channel is left untouched and only colour edges are sharpened. JPGs have no transparency, so any clear areas become white.

JPG, PNG and WebP. The download keeps the same format you uploaded.

No. The sharpening runs entirely in your browser with the Canvas API. Nothing leaves your device and it works offline once the page has loaded.

Sharpening processes every pixel, so very high-resolution images take a moment on slower devices. Typical photos and screenshots sharpen almost instantly.