PDFs and conversion

How to convert PNG to JPG on a Mac

Updated 25 October 2026 · 3 min read

Convert PNG to JPG with Preview, Finder's Convert Image or sips, what happens to transparent areas, and how Orrel converts between image formats from a right-click.

Mac screenshots and many downloaded images are PNG files. PNG keeps every pixel exactly, which makes photos large. JPEG trades a little detail for much smaller files, and some upload forms accept nothing else. Converting is quick on a Mac; the one thing to watch is transparency.

Preview, with a quality slider

1. Open the PNG in Preview.
2. Choose File › Export.
3. Set Format to JPEG and drag the Quality slider. The file size updates as you move it.
4. Click Save. The PNG stays as it was.

For several images, open them together in one Preview window, select all the thumbnails in the sidebar, and choose File › Export Selected Images. Click Options to choose JPEG.

Finder's Convert Image

On macOS 12 Monterey and later, select one or more PNGs, Control-click and choose Quick Actions › Convert Image. Choose JPEG, an image size and whether to keep the metadata, then click Convert to JPEG. The JPGs appear beside the originals.

sips in Terminal

cd ~/Desktop
for f in *.png; do sips -s format jpeg "$f" --out "${f%.*}.jpg"; done

Add -s formatOptions 80 before --out to set the quality, from 0 to 100.

Transparency

PNGs can have transparent areas, such as a logo with no background. JPEG cannot, so every tool has to fill them with something. Preview, sips and Orrel fill them with white, which looks right on a white page and wrong on a dark one. Check logos and icons after converting. If you need transparency in a smaller file, convert to HEIC instead, or keep the PNG.

How Orrel does it

Control-click a PNG in Orrel, drop it on Orrel's Dock icon, or choose Orrel from Finder's Quick Actions, and the ring offers the other image formats. Pick JPEG and press Return.

• Formats. JPEG, PNG, HEIC, TIFF, GIF and BMP. WebP is offered only on macOS versions that can write it.
• Transparent areas become white when converting to JPEG or BMP; PNG, HEIC, TIFF and GIF keep transparency.
• Batches. Select many images and convert them in one go. New files appear beside the originals, which are never changed.
• Compress instead. If the aim is a smaller file, Compress re-saves a PNG as JPEG at High, Medium or Small quality, or as HEIC if it has transparency, and keeps it only if it is smaller.
• Remove metadata. Strip camera details and location before sharing a photo.

Where Orrel stops

Orrel converts between the formats macOS itself can write. It does not write AVIF, and WebP depends on the version of macOS. There is no quality slider for conversions; for a precise quality or file size, use Preview's Export. It cannot choose a background colour for transparent areas, and it is not an image editor. If you are converting only PNG screenshots, Finder's Convert Image does the job well on its own.