Image Corners

📖 Tool Introduction

Image Corners is an in-browser rounding tool for turning rectangular photos, screenshots and card graphics into the soft, friendly corner style that modern apps love. Unlike the usual four-equal-radius tools, this one treats the top-left, top-right, bottom-left and bottom-right corners as fully independent values. You can blow up just the top-right corner to fake a folded tag effect, stretch one corner into a half circle for an asymmetric card, or keep all four equal when that is what the design needs. Each radius is typed into a number field or nudged with stepper buttons that move five pixels at a time, anywhere from zero to two hundred pixels, and a sync checkbox mirrors any corner adjustment to the other three. The cut itself is built corner by corner with arcTo calls on a Path2D path clipped to the canvas, so large radii never swallow each other or warp the shape the way a naive rounded-rect approximation can. The result exports as PNG, and everything outside the rounded corners is genuinely transparent, which means you can drop the file straight onto a webpage, a presentation slide or a chat message without trimming a white rectangle around it. Every calculation happens in local memory, so screenshots containing sensitive details are processed on the device itself. Where does this fit in daily work? Designers pasting a screenshot into a slide deck want its corners to match the soft cards around it; app makers need a preview of how a rectangular ad will look inside a rounded container; and anyone assembling a gallery on the web prefers images that already carry their corners, so CSS hacks are unnecessary. Independent radii unlock details a simple CSS border-radius cannot: a folded-tag look comes from rounding only the top-right corner, a chat-bubble hint from a single larger corner, and a gently asymmetric card feels hand-built rather than templated. Stepper buttons move five pixels at a time so the shape settles with a few clicks, and the sync checkbox collapses the four corners into one value whenever a uniform radius is what you want. Outside the corners the PNG stays transparent, so the rounded picture drops onto any background color or pattern without a white frame.

✨ Key Features

• Independent corners: top-left, top-right, bottom-left, bottom-right set separately
• One-tap sync: tick it and one adjustment applies to all four
• Stepper nudges: type a number, or move five pixels per click
• Precise path: corner-by-corner arcTo stays true at large radii
• Transparent edges: outside the rounded corners the PNG is truly clear
• Live preview: every tweak repaints instantly, what you see is what you get

📝 How to Use

1. Click the drop zone to upload a rectangular photo or screenshot
2. Type radii into the four corner fields, or nudge them with the buttons
3. Tick Sync all corners if you want them equal
4. Check the preview until the rounding looks right
5. Click Export PNG to save the rounded image

⚠️ Notes

• Radius cap: a single corner tops out at 200px and clamps past half an edge
• Transparency: only PNG keeps the clear corners; JPEG fills them white
• Working size: huge images are scaled to a 2048px long edge first
• Asymmetric cards: raise one corner only to build a folded-tag shape
• Original stays safe: all clipping happens in memory, the local file is untouched