Sharpen Images Online
Make photos crisper with an unsharp-mask convolution kernel. Adjustable strength brings back micro-detail.
About the Sharpen Image
Sharpening applies a 3×3 unsharp kernel that boosts contrast along edges — exactly how camera JPEG sharpening works. Slightly soft photos (resized, scanned, upscaled) gain snap at 40–80%; push higher for crunchy textures or artistic punch.
How it works
The tool convolves your image with an unsharp-mask kernel: it detects edges by comparing each pixel against its neighbors and boosts local contrast along them. The result reads as sharper micro-detail — text gains definition, foliage separates, and slightly soft resizes recover snap.
How to use it
Add up to 10 images, set the sharpening amount (modest values look natural; high ones add halos), and process. Zoom into a preview to check for halos before downloading.
Supported formats & limitations
Accepts .jpg, .png and .webp up to 30MB each, 10 per run. Sharpening amplifies existing JPEG artifacts and sensor noise — very compressed sources may need a gentler setting. It cannot truly rescue heavily blurred images; think 'enhance', not 'restore'.
Common use cases
Final polish after downsizing (resizing always softens slightly), making scanned documents' text pop, sharpening product photos for marketplace listings, and adding bite to landscape shots straight out of camera.
Frequently asked questions
How private is Sharpen Image?
Everything runs locally in your browser via the Canvas API. Your picture never leaves your machine — there is no upload step at all, so processing is as private as working in an offline editor.
Which input formats does Sharpen Image accept?
Common formats are covered: JPG, PNG or WEBP, each up to 30 MB. Paste from the clipboard, drag and drop, or use the select button.
What are the size and batch limits?
Up to 10 images per batch, 30 MB per file, and unlimited runs — no signup, no counters, and no watermark stamped on results.
Can I fine-tune the result before downloading?
You can adjust Sharpen strength. Results are previewed after processing, so tweak values and re-run until the output looks right.
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