Make Rounded PNG Corners with a Transparent Background

Use the Rounded Corner Cropper to cut curved corners into an image and save them as real PNG transparency. Keep the background set to Transparent. You can give all four corners the same radius or adjust each one separately.

A rounded preview on a website does not necessarily mean the saved image has rounded corners. A page can hide square corners with its own styling. The important check is the downloaded PNG: its outer corner pixels must be transparent if you want the image to work on different backgrounds.

Two actual exports on two backgrounds

Both images came from the same original 256 × 256 px illustration. We exported them through the tool in Chromium 139. The equal-corner file contains 962 fully transparent pixels; the opposite-corner file contains 2,012. Both also have partially transparent edge pixels that make the curves look smooth. Neither dark nor light preview panel is part of the download.

The square source PNG contains no transparent pixels. Download it to repeat the comparison. The measurement record includes the controls and file sizes.

Make all corners equal

1. Upload the source image and wait for its canvas preview.
2. Leave Link all corners selected. One slider change then applies to all four corners.
3. Set Background to Transparent. The initial radius is 40 px, which is the first sample above.
4. Move a radius slider slowly while you watch the subject. Stop before the curve removes a face, logo, or other needed detail.
5. Select Download PNG. Open the downloaded file on a contrasting background.

For our small portrait, 40 px removes only a modest area. The same number on a wide banner has a different visual effect. Choose the radius against the actual output, not against a rule that every image should use one number.

Round selected corners

Clear Link all corners. The four sliders now work independently. To reproduce the second sample, set Top left to 80 px, Top right to 0 px, Bottom left to 0 px, and Bottom right to 80 px. A zero radius leaves that corner square.

This is useful for a small card or a graphic that sits against a page edge. It does not add a speech-bubble tail, cut out the person, or remove the image's interior background. The amber background inside our portrait remains opaque. Only the areas outside the curved boundary are cut away.

Check size and radius before export

The current tool limits the output width to 900 px and reduces the height in proportion. It does not enlarge smaller sources. Our 256 px source therefore stays 256 px wide. If your original is much larger, the downloaded file may be smaller than the source even though you only changed the corners.

The radius controls allow values up to 400 px. That range is not a guarantee that every value suits every image. On a small picture, very large radii can meet or overlap and produce an unexpected shape. Begin with a small radius, inspect each edge, and reduce it if the contour looks wrong.

Keep the source file as well as the cropped result. Once a corner is transparent, the removed image detail is no longer in that output. Reopen the original if you want a smaller curve later.

Avoid a white box after download

Keep PNG as the file format when transparency matters. Do not turn the result into a screenshot or save it as JPEG, because that can make the background solid. Selecting White, Black, or Soft Gray in this tool deliberately fills the output behind the image. Select Transparent for an empty corner.

Finally, test the file where you will use it. Some apps place all avatars in their own circle or rounded box. That extra mask can hide your careful corner shape. For custom emoji, also inspect it at small size: a curved photo border may use space that the face needs. The transparent versus solid background guide helps you choose which treatment fits the artwork.