How to Convert PNG to WebP on Mac

What you need

• macOS 14.0 or later
• PixPack – Image Compressor Pro from the Mac App Store
• PNG source files

Step by step

1. Add the PNG files

   Add the PNGs with Add Files, or drag the folder that contains them into the PixPack window.

2. Set the output format to WebP

   Choose WebP in the format options. The Format Advisor can also recommend a format if you want a second opinion.

3. Choose the quality

   Start from the Web preset, then adjust the quality slider while watching the preview. Smart Recommend Quality will pick a level for you.

4. Decide about metadata

   Leave keep-metadata off for the smallest files, or enable it if you need EXIF data preserved. WebP exports preserve EXIF when keep metadata is enabled, as of version 1.4.3.

5. Optionally resize

   Set a maximum width and height if the PNGs are larger than the layout will ever display.

6. Export

   Apply to All Files, then export the WebP files to your chosen output folder.

Does converting PNG to WebP lose transparency?

No. WebP supports an alpha channel, so transparency in the source PNG is preserved in the WebP output. This is one reason WebP is a better fit than JPEG for UI assets and logos.

Lossy or lossless WebP

PixPack exposes a quality slider, which implies a lossy encode. If you need to preserve exact pixels, keep the PNG as the master and treat the WebP as the delivery format.

When to keep PNG instead

• The destination does not accept WebP
• You need a lossless master for archival
• A downstream tool requires a .png extension

Expected result

A set of WebP files converted from your PNG sources, at the quality and dimensions you selected, with the size reduction reported per file.

Tips

• Convert into a separate output folder so the original PNGs stay available.
• Compare a couple of images in slider mode before converting an entire asset library.
• For a web project, combine the conversion with a maximum width that matches your layout.