OneTaskBy Tim King · Updated
Round Corners Image Tool
Add Rounded Corners to a Photo or Crop It to an Oval, Transparent Background
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How the Round Corners Image works
This round corners image tool trims the sharp corners off a photo, screenshot or logo and leaves smooth curves with a transparent background, ready for slides, app mockups, websites and social posts where a soft card look fits better than square edges.
How to round corners image files
Choose an image and the rounded version appears straight away. Drag Corner radius to set how big the curves are, measured as a percentage of the shorter side so the look stays consistent on any size of picture. At 50% a square image becomes a perfect circle.
Transparent or solid corners
Transparent saves a PNG where the trimmed corners are see-through, which is what you want for web pages, presentations and design apps. Choose White or Black when the image is going somewhere that cannot show transparency, such as an email or a print layout.
Circle or oval crops
Switch Shape to Circle or oval to crop the whole picture into an ellipse that touches all four edges. For a perfect circle start from a square image, or use the circle crop tool to pick the area.
Private by design
The corners are clipped on a canvas in your browser, and the image is never uploaded.
FAQ
Why is my rounded image a PNG?
JPG cannot store transparency, so the corners would turn black or white. With a transparent background the result is always a PNG. If you choose a solid background the output follows the original format.
How do I match the CSS border-radius of my website?
Work out your border radius as a share of the image's short side. A 12 pixel radius on a 300 pixel tall image is 4%, so set the slider to 4 and the downloaded image will match the rounded cards on your page.
Can I round only some corners?
This tool rounds all four corners by the same amount, which is the common app icon and card style. For uneven shapes, use an image editor with a custom mask or crop the image before rounding it.
Will rounding reduce image quality?
No. Only the pixels outside the curve are removed, and the edges are anti-aliased so they look smooth. Images up to 2,400 pixels on the long side keep their original size.
See also: all Images tools, Audio, Video & Screen, PDF, SVG, Simulations & Screensavers, Generative Art, Chart Makers, 3D Model Viewers, Drawing Pads, Mockups & 3D Making, Diagram Makers, 3D Science, Tracker Music.
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