Sharpen image
Crisper edges, smooth skin and sky — preview before you save.
Drop files here
or click to choose from your deviceAccepted: JPG, JPEG, PNG, WEBP, AVIF, GIF, BMP, HEIC, HEIF
Up to 3 files per runUp to 20 MB per file5 runs per dayRemove limits with Pro✓ Works offline
Your files stay on your device
This tool runs entirely in your browser. Nothing is uploaded, nothing is stored, and you can even turn off your internet connection before you start.
Example
Example: a slightly soft photo at the default settings
A phone photo a touch out of focus. Amount 60, radius 1 px and threshold 4 are the defaults; check the before/after preview at 100 % before pressing Sharpen.
- The defaults push the pixels either side of an edge apart, from 100 and 160 to 89 and 171: more contrast right at the edge.
- Fine grain only 3 levels high stays as it is with threshold 4; at threshold 0 it is sharpened too.
| Setting | Pixels beside an edge from grey 100 to 160 |
|---|---|
| Before | 100 | 160 |
| Defaults: amount 60, radius 1 px | 89 | 171 |
| Amount 120 | 78 | 182 |
| Radius 2 px | 98, 92, 86 | 174, 168, 162 |
The defaults suit most photos: raise the amount for a softer one, lower it if light or dark outlines appear. A larger radius widens the effect over more pixels, for large, soft detail.
How it works
- Add one or more photos — JPG, PNG, WebP or HEIC.
- Adjust the amount and radius while you watch the before/after preview at 100 %; raise the threshold if noise or skin starts to look rough.
- Press Sharpen and download the pictures, named with “-sharpened”.
Frequently asked questions
- What does sharpening do?
- It makes edges crisper by increasing contrast right at them (an “unsharp mask”). It brings back the softness of a slight focus miss, a phone or scanner picture, or a photo that was just resized — it can’t recreate detail that was never there.
- Which settings should I use?
- Start with amount 60 and radius 1. Use a larger radius for soft, large detail and a smaller one for fine texture. If bright or dark outlines appear along edges, lower the amount.
- Why does the threshold matter?
- It leaves small differences alone, so skin, sky and noise stay smooth while real edges get sharper. Raise it for noisy or high-ISO photos.
- My photo is very blurry or tiny — will this help?
- Only a little. For very blurry, low-resolution or pixelated pictures, the AI enhancer rebuilds detail better; sharpen afterwards if needed.
- Why do light or dark outlines appear along edges?
- Too much sharpening: the pixels beside an edge are pushed further apart than looks natural. On an edge from grey 100 to 160, amount 60 gives 89 and 171, amount 120 gives 78 and 182. Lower the amount or the radius.
- Does sharpening change the colours?
- No — only brightness is sharpened. The same amount is added to red, green and blue, so the colour stays and edges don’t pick up coloured fringes.
- Are my photos uploaded?
- No. They are sharpened in your browser and never leave your device.