How to Convert PNG to JPG on Mac

PNGs are the default format for Mac screenshots, but they take up a lot of space. A single Retina screenshot can weigh 5 to 10 MB, which adds up fast when you share work in Slack, attach files to email, or upload images to a website. Converting those PNGs to JPG is a quick win that often cuts file size by 70 percent or more.

The good news: macOS has two solid built-in methods, and a dedicated converter covers everything else. Here is how to pick the right one.

Method 1: Using Preview (Best for One File)

Preview is already on your Mac and handles single conversions in seconds.

Double-click the PNG to open it in Preview.
Go to File > Export.
Open the Format dropdown and select JPEG.
Drag the Quality slider to around 80 percent for a good balance of size and clarity.
Click Save and choose where to keep the new file.

Preview gives you direct control over quality, which makes it a good choice when one specific image matters, such as a portfolio piece or a featured blog image.

Method 2: Using Finder Quick Actions (Best for a Few Files)

If you have a handful of images and do not want to open each one, Finder can convert without launching any app.

Select one or more PNGs in Finder.
Right-click and choose Quick Actions > Convert Image.
Pick JPEG as the format and choose an image size (Actual Size keeps full resolution).
Click Convert to JPEG.

macOS saves the converted copies next to the originals, so your source PNGs stay untouched.

Method 3: Using imgKonvert (Best for Batches)

When you have dozens of screenshots or a folder of product photos, converting one by one wastes time. A batch converter handles the whole set at once.

Open the PNG to JPG converter.
Drag and drop all your PNG files from Finder.
Click Convert All.
Download your optimized JPGs in one go.

The tool is privacy-focused and performant, and no data leaves your device during conversion.

PNG vs JPG: When to Convert (and When Not To)

Situation	Keep PNG	Convert to JPG
Screenshots with text or UI	Yes, text stays crisp	No, edges can look fuzzy
Logos or graphics with transparency	Yes, transparency survives	No, transparency becomes a solid color
Photographs and camera images	Rarely worth it	Yes, much smaller files
Blog and website images	Only for graphics with text	Yes, faster page loads
Email attachments	Only if transparency matters	Yes, smaller attachments send faster

The rule of thumb: convert photos and complex images to JPG, and keep graphics with text or transparency as PNG. If a PNG photo is headed for the web, run it through the image compressor after converting to trim even more weight.

Common Mistakes to Avoid

Converting a logo with transparency

JPG has no transparency channel. A transparent PNG background becomes solid white (or black) after conversion. If the transparency matters, keep the PNG or convert to WebP instead.

Using maximum quality for every image

Exporting at 100 percent quality produces a JPG nearly as heavy as the original PNG. For screen use, 75 to 85 percent is visually identical and far smaller.

Deleting the originals immediately

Keep the source PNGs until you have checked the JPGs. JPG compression is permanent, so you cannot restore detail later. Archive originals for print work and reuse.

Uploading giant PNGs and hoping the platform fixes them

Social networks and CMS platforms re-compress uploads on their own terms. A pre-sized, pre-compressed JPG gives you far more control over the final result.

Frequently Asked Questions

Will converting PNG to JPG reduce quality?

Slightly, because JPG uses lossy compression. At 80 percent quality the difference is invisible on screens for photographs. For text-heavy graphics, keep the PNG to avoid fuzzy edges.

How much smaller will the JPG be?

Photos typically shrink by 60 to 80 percent. A 8 MB PNG screenshot often becomes a 1 to 2 MB JPG with no visible change on screen.

Can I convert back from JPG to PNG?

Yes, but converting back does not restore lost detail or transparency. Treat PNG to JPG as a one-way trip and keep backups of files you may need to edit.

Do I need to install anything on my Mac?

No. Preview and Finder Quick Actions are built into macOS. For batch work, the free PNG to JPG converter needs no install and no account.

Conclusion

For a single file, Preview gives you quality control and Finder Quick Actions give you speed. For batches of screenshots, photos, or website assets, imgKonvert converts everything at once with secure, privacy-focused processing. Pick the method that matches the size of the job and you will never fight bloated PNGs again.

How to Convert PNG to JPG on Mac