Add Rounded Corners Online

Add rounded corners to images with customizable radius.

What Rounded Corners Does

Rounded Corners works by masking, not reshaping. The tool draws an arc into each of the four corners of your image and sets every pixel outside that arc to fully transparent, while the rest of the image stays untouched pixel-for-pixel — no color shifting, no resampling of the areas you keep. The Corner Radius value controls how far that arc cuts inward: a small radius clips only a sliver from each corner, and a radius close to half the shorter edge of the image produces a near-pill or fully circular shape. Because the effect depends on transparency, the export format matters as much as the radius you choose. JPG has no alpha channel, so if you download the result as a JPG, the corner regions that should be see-through get filled in with a solid color instead, and the rounding disappears visually even though the arc was still calculated correctly. PNG is required to actually preserve the transparent corners once you leave the editor. The tool does not crop, resize, or recompose the image — the canvas dimensions after processing are identical to what you uploaded, the rounded areas are just holes in the alpha channel. It also has no awareness of what's in the image: it won't detect a face, a logo, or text sitting near a corner, so the arc cuts through image content exactly the same way it cuts through empty background. And because the Corner Radius setting is a single value, it applies uniformly — there's no built-in way to make one corner more rounded than the others.

When You Need the Rounding Baked Into the File

CSS border-radius handles rounded corners fine on a live webpage, but plenty of contexts can't rely on a browser to render it. Email clients routinely strip or ignore border-radius, so a rounded product photo or avatar in a marketing email only looks rounded if the file itself already carries transparent corners. The same limitation shows up in PDFs, native app views that display images as-is, slide decks, and social platforms that render uploaded assets without applying your site's stylesheet. App icon and favicon work is another recurring case. Some platforms auto-mask a square PNG for you, but for preview assets, marketing screenshots of an icon, or surfaces that don't apply their own mask, rounding the source image yourself keeps things visually consistent with the masked version users actually see. Avatars and profile images follow the same logic: if you're compositing a rounded avatar into a larger flattened graphic — a certificate, a name badge, a card layout exported as one image, a video thumbnail — the rounding has to exist in the source pixels before flattening, because a CSS radius applied only to the original element won't survive being baked into a static export. Because processing happens entirely in your browser, this also works for material you'd rather not send to a server — screenshots containing personal information, unreleased product photography, or internal tooling assets — none of it is transmitted anywhere in order to get the corners rounded.

Uniform corner radius across all four corners in one adjustment
Live preview of the exact cut before you export anything
Transparency preserved for compositing onto any background
Processed locally in the browser, nothing uploaded

How to Round the Corners

Rounding takes one setting and one export decision — there's no layer or mask to manage by hand.

1

Upload the image you want to round.

2

Drag the Corner Radius slider, or type a pixel value directly — all four corners update together.

3

Check the live preview, paying attention to any content sitting close to the edges.

4

Download the result as PNG so the transparent corners are preserved — a JPG export will fill them in instead.

Rounded Corners FAQ

JPG has no alpha channel, so it can't store transparent pixels. When you export to JPG, the areas the tool cut away get filled with a solid color instead of staying see-through, which erases the rounded look even though the radius was applied correctly. Export as PNG whenever you need the corners to actually render as rounded, especially if the image will sit over a background other than solid white.
Crop removes pixels outside a selection and shrinks the canvas to match, so the image's dimensions change. Rounded Corners leaves the canvas size untouched and instead makes the four corner regions transparent, so the file's width and height are identical before and after. If you want a specific aspect ratio and rounded corners together, crop first, then round — doing it the other way around can leave uneven margin at the corners.
iOS icons use a continuous squircle curve, not a plain circular arc, so no Corner Radius value here reproduces it exactly. As a rough visual approximation, a radius around 18-22% of the icon's width gets close for a standard app-icon look — for a 1024px icon that's roughly 180-225px. For a pixel-accurate platform icon, use the platform's own masking rather than this tool.
No. Rounded Corners runs entirely in your browser using canvas processing, so the image data never leaves your device or touches a server. That makes it fine for screenshots or photos you don't want transmitted anywhere, including ones containing personal information.
Not with this tool — the Corner Radius setting applies the same value to all four corners at once, so asymmetric rounding isn't an option here. If you need one corner rounded differently, you'd have to round uniformly and then handle the remaining corner separately in a layer-based editor.
You can upload common raster formats like JPG, PNG, and WebP — the upload format doesn't affect how the radius is calculated. The export format is what matters: always download as PNG if you need the rounded corners to show as transparent rather than filled in.
The arc cuts through whatever pixels are there — the tool has no idea what's a subject and what's background, so a face, logo, or line of text sitting near a corner gets clipped along with everything else outside the curve. Check the live preview at your intended radius before exporting, and lower the radius or reframe the source image if it's cutting into something you need to keep visible.
The effective radius caps out at half the length of the image's shorter side. Past that point the two arcs along that edge would overlap, so the tool holds the radius there, giving you a fully rounded pill or circular end on that dimension instead of an invalid result.

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