How to Add a Border to an Image on Mac in Your Browser

If you need a simple white, black, colored, or semi-transparent frame around a photo, ShowPro's Add Border to Image tool can create it directly in your Mac browser.

Open: https://showprosoftware.com/tools/add-border-to-image

What the tool does

The current tool:

It does not draw the border over the original pixels. The border is added outside the original image dimensions.

Example dimensions

If your source image is 1200 × 800 and you add a 20 px border, the output is:

1240 × 840

because 20 pixels are added to the left and right, and 20 pixels to the top and bottom.

Add a white photo border

The result downloads as a PNG.

Add a translucent border

Lower the Border Opacity control.

Because the output is PNG, transparency in the border can be represented. Whether it looks transparent in another app depends on how that app displays PNG alpha.

Supported source images

The file picker accepts image files that the browser reports as images.

Actual decoding depends on the browser. Common formats such as JPEG, PNG, WebP, GIF, and BMP are broadly supported in modern browsers, but specialized formats can vary.

For HEIC compatibility, see https://showprosoftware.com/blog/heic-compatibility-matrix-2026.

Image quality and format

The original visible image is drawn to an HTML canvas at its decoded dimensions and the result is encoded as PNG.

That means the tool does not preserve the source file's original compression stream or metadata containers.

Keep your source image if archival metadata or the exact original encoding matters.

High-resolution images

Very large images require more browser memory.

The current tool warns when the decoded image exceeds 20 million pixels, but it does not automatically shrink the source.

If your browser struggles with a very large image, resize a copy first at https://showprosoftware.com/tools/image-resizer.

Browser-local processing

The border operation uses browser image and canvas APIs. The selected image is not sent to a ShowPro border-processing endpoint for this operation.

Normal site analytics, ads, billing, and other networked functionality are separate.

FAQ

Does adding a 20 px border cover 20 px of my photo?

No. It expands the canvas by 20 px on each edge and draws the original image inside.

Can the border be transparent?

Yes. The opacity control supports partial transparency.

What format downloads?

PNG.

Can I choose any color?

The interface provides a standard color picker plus opacity.

Is the image uploaded for border processing?

The current operation runs in browser canvas code rather than a ShowPro image-processing endpoint.