Upload an image to sharpen
Accepted formats: JPG, PNG, WEBP, BMP, GIF (non-animated)
Paste (Ctrl/⌘+V) or drop an image — or import from a URL
Sharpening makes an image look crisper by increasing the contrast along edges, where light meets dark. Image Machine uses an unsharp mask — the same technique professional photo editors use — which compares each pixel to a blurred version of the image and boosts the difference. Three controls give you precise command: Amount sets how strong the effect is, Radius sets how wide the sharpened edge halo becomes, and Threshold lets you sharpen only the meaningful edges while leaving smooth areas like skin or sky free of amplified noise. It is the right tool for rescuing slightly soft photos, crispening scans, or adding bite to web and print images. Everything runs locally in your browser, so your photo is never uploaded, and transparent PNG areas stay transparent.
How It Works
Choose a tool
Pick from 120+ tools to resize, convert, compress, or enhance your image.
Upload & edit
Drag and drop your image and adjust the settings. It stays on your device.
Download
Save your result instantly — no watermark, no sign-up required.
Why Image Machine?
Your files never leave your device
All processing runs locally in your browser. Your images are never uploaded to a server.
Completely free
Every tool is free, with no limits, no watermarks, and no hidden costs.
Lightning fast
No upload waiting — your images are processed instantly on your own device.
Professional quality
Pixel-perfect output with full control over format, size, and quality.
Frequently Asked Questions
What is an unsharp mask?
Despite the name, an unsharp mask sharpens an image. It works by blurring a copy of the image, subtracting that blur to find the edges, and then increasing the contrast along those edges. This is the standard, high-quality sharpening method used in professional photo software because it enhances detail without the harsh, blocky artifacts a simple sharpen filter can produce.
How do I sharpen without adding noise or halos?
Start with a moderate amount (around 100%) and a small radius (1–2 px), then raise the threshold until grainy, smooth areas like sky or skin stop sparkling. A large radius or a very high amount creates visible bright and dark halos along edges, so increase them gradually and stop as soon as the detail looks crisp. The threshold control is the key to sharpening real edges while leaving flat areas clean.
Is my image uploaded anywhere?
No. Sharpening is applied entirely in your browser using your device's own processor. Your photo never leaves your computer, nothing is sent to a server, and transparent PNG areas stay transparent.