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How to convert JPG to PNG on a Mac, and what it does not fix
By Himanshu Ranjan · Updated 8 November 2026
On a Mac, open the JPG in Preview and choose File > Export with PNG as the format, or select a batch in Finder and run Convert › Convert to PNG in FileDial. The conversion is local. Be aware that PNG cannot restore detail a JPG already lost, and it will not add transparency by itself.
What converting JPG to PNG actually does
A JPG is lossy: saving it threw away some detail, and Wikipedia notes each re-save of a lossy JPG can lose more. A PNG is lossless, so it stores the pixels exactly as they are at the moment you convert. That means the PNG is a faithful copy of the JPG, artefacts included. It is not a higher-quality version of the photo.
The practical reasons to convert are different: an editor or print workflow that demands PNG, a need to stop further JPG recompression while you edit, or a design tool that treats PNG as the working format.
Convert with FileDial
Select one file or a whole folder of JPGs. FileDial writes a new PNG beside each, keeps the originals, and shows the size before and after on a result card. PNG files of photographs are much larger, so expect that number to go up.
- Select the JPG files in Finder.
- Hold the right Option key to open the dial, or right-click and choose Open in FileDial.
- Choose Convert, then release on Convert › Convert to PNG.
- Open the PNG copies beside your JPGs. Undo removes them if you change your mind.
Convert with Preview or a Quick Action
In Preview, open the JPG, choose File > Export, pick PNG in the Format pop-up and click Save. Multiple images can be exported together if they are open in one window and selected in the sidebar.
Finder also has a built-in route. Control-click the file, choose Quick Actions, then More and Convert Image, and pick a format and size. Apple's help page says you can use it to convert an HEIC photo to JPEG or PNG, so the same menu is worth checking for JPG input on your version of macOS.
What will not change
If you hoped the PNG would have a transparent background, it will not. A JPG has a solid background baked in, and conversion keeps it. To cut out a subject you need a separate step: Adjust › Remove background in FileDial saves a transparent PNG beside the original.
Do not convert photos to PNG to make them smaller either. The file will usually grow. If size is the goal, go the other way and use Compress › Compress, or see the compress image article.
- Detail lost in the JPG stays lost.
- Transparency is not created, only supported.
- File size normally increases for photographs.
When PNG is genuinely the better choice
There are a handful of jobs where PNG earns its larger size. Screenshots with text keep crisp edges. Graphics with flat colours and sharp lines avoid the smudging JPG creates around edges. Images you will edit repeatedly are safer in PNG, because each save does not recompress them lossily. And some tools, including icon, sticker and game-asset workflows, simply require PNG.
If your picture is a photograph that you only need to share, stay with JPG. Wikipedia describes JPG as adjustable between size and quality, with about 10:1 compression usually acceptable and aggressive settings showing blockiness near sharp edges like text. That blockiness is the reason text-heavy images belong in PNG, and the reason photographs do not. A useful rule is to look at what is in the picture: if it is mostly camera light, JPG, and if it is mostly drawn or typed, PNG.
- Text and UI: PNG.
- Photographs for sharing: JPG.
- Repeated editing: PNG, then export JPG at the end.
Mistakes to avoid
Converting a JPG to PNG, then back to JPG, then to PNG again, gains nothing and costs time. The JPG stage is where loss happens, and every trip back through it adds more. Another mistake is picking PNG to make a picture sharper. Sharpness comes from the source and from tools such as Adjust › Sharpen, not from the container.
Preview is the right answer for one or two images. FileDial is the better fit when you have a folder, when you want undo and a size report, or when PNG is just the first step in a chain, such as converting and then running Adjust › Remove background. If file size is a concern, remember PNG of a photo can be very large, so check the result card before you send or upload anything.
Keeping it private
Uploading a personal photo to a free converter hands it to a stranger's server. FileDial runs on your Mac, files are never uploaded, and everything works offline.
Questions
Does JPG to PNG improve quality?
No. PNG is lossless, which means it preserves the pixels exactly as they are, including any compression artefacts from the JPG. You get a faithful copy at a bigger file size, not a sharper or cleaner image. Upscaling or enhancement tools are a different job.
Why does my PNG look the same but weigh much more?
PNG stores every pixel without discarding detail, while JPG removes information the eye tends to miss. For photographs with lots of fine texture and noise, that can mean several times the size. PNG is better suited to screenshots, logos and flat graphics.
Can I get a transparent background by converting?
Not by conversion alone. JPG has no alpha channel, so the background is already solid. Use a background removal step first. In FileDial that is Adjust › Remove background, which saves a transparent PNG beside the original. After removal the PNG can sit on any slide or web background, because the cutout carries its own transparency instead of a flat fill.
Is there a batch option without installing anything?
Preview can export several images at once when they are open in a single window and selected in the sidebar. Finder's Quick Actions also offer Convert Image on selected files. FileDial is useful when you want a dial, undo and a size report for large folders.