How to convert JPG to PNG on Mac (batch, offline, 2026)

The upload portal says “PNG only.” The developer asks for the asset “as a PNG, not a JPG.” A design tool complains about compression artifacts in the logo someone supplied as a JPEG. Or you’re about to run an image through a fifth round of edits and someone finally points out that every JPG re-save quietly chews away a little more detail.

Whatever the trigger, the fix is the same conversion: JPG to PNG, and on a Mac it’s available in four sizes — a Preview export, a Finder right-click, a Terminal one-liner, and a drag-the-folder batch app. This guide covers how to convert JPG to PNG on a Mac by every route, and — just as important — what the conversion does and doesn’t do, because JPG-to-PNG carries two stubborn myths that waste people’s time.

What PNG actually fixes (and the two things it can’t)

PNG is a lossless format: whatever pixels go in are stored exactly, forever, through any number of re-saves. JPG is lossy: every save discards a little detail, and edits-plus-re-saves compound the damage. That asymmetry is the entire reason this conversion exists, and it points at the situations where it genuinely makes sense:

• The destination demands PNG. Upload portals, app stores, CMS asset pipelines, print-on-demand services, government forms — plenty of systems whitelist PNG and reject JPEG, full stop.
• The image is entering an edit loop. Convert to PNG before the cropping, annotating, and re-saving starts, and generation loss stops at whatever the file has already suffered. This is why designers ask for PNG: not because it looks better today, but because it can’t get worse tomorrow.
• The image is a graphic that should never have been a JPG — a logo, chart, or screenshot that someone exported as JPEG, complete with the fuzzy halos JPG paints around sharp edges. PNG is the right home for it going forward (though see myth #1 below about the halos already baked in).

And here are the two things the conversion cannot do, no matter which tool performs it:

1. It can’t restore quality. The detail a JPG encode discarded is gone; PNG faithfully preserves the file as it now is, artifacts and all. Converting to PNG is a tourniquet, not a heal — it stops further loss, it doesn’t undo old loss. If the JPG looks blocky, the PNG will look identically blocky while being five times larger.
2. It can’t create transparency. This is the big one. JPG has no alpha channel, so a JPG’s background is ordinary opaque pixels — converting to PNG produces an image that could hold transparency but doesn’t. If what you actually need is a logo with a see-through background, the conversion alone won’t get you there; you need background removal first (macOS has a built-in Remove Background Quick Action in Finder’s right-click menu, and it outputs PNG automatically — for anything intricate, a real editor does it better). Convert-to-PNG is how you keep transparency an editor created, not how you create it.

Known limitations acknowledged — here’s every way to do it, lightest to heaviest. All of them run offline.

Skip the converter websites

The search results for “jpg to png” are crowded with free web converters, and the arithmetic against them is even worse than usual here: PNG output is bigger than the JPG you started with — often 3–8× bigger — so you’re uploading your photos to a stranger’s server and then downloading back several times the data, to perform a conversion your Mac does locally in milliseconds with tools that shipped preinstalled. For client work, product shots, or anything with people in it, keep it on the machine.

Method 1: Preview (one or two images)

1. Double-click the JPG — it opens in Preview.
2. Choose File → Export.
3. Set Format to PNG. (If PNG isn’t listed, hold Option while clicking the Format menu to reveal the full list.)
4. Click Save.

No quality slider appears, because PNG doesn’t have quality levels — lossless is lossless. For a handful of files: open them together in Preview, ⌘A in the thumbnail sidebar, File → Export Selected Images, then Options to set PNG. Fine for a dozen; tedious past that.

Method 2: Finder’s Quick Action (fastest free batch)

1. In Finder, select the JPGs — or ⌘A on the folder’s contents.
2. Right-click the selection.
3. Choose Quick Actions → Convert Image.
4. Set Format to PNG, pick a size (Actual Size keeps full resolution), and decide whether to keep metadata.
5. Click Convert to PNG.

New .png files land beside the originals, which stay untouched. For the occasional folder this is the best free answer on macOS. Its limits are the usual ones: JPEG/PNG/HEIF outputs only, coarse size presets, and no renaming — output files inherit the input names.

Method 3: sips in Terminal (scripted batches)

macOS ships sips, a command-line image converter. One file:

sips -s format png photo.jpg --out photo.png

A whole folder:

cd ~/Pictures/to-convert
for f in *.jpg; do
  [ -e "$f" ] || continue
  sips -s format png "$f" --out "${f%.*}.png"
done

There’s no quality flag to remember for PNG output — lossless has no dial. sips is fast, free, and preinstalled, and also unforgiving: no preview, no undo, and a mistyped --out overwrites files. Use it in scripts, not by hand on originals. If automation is the real goal, Zumkor’s “Convert Files” action in Apple’s Shortcuts app does the same job headless — a folder-watch shortcut converts whatever lands in a folder, without the overwrite risk.

Method 4: Zumkor (drag the folder, done)

When JPG-to-PNG is a recurring chore — assets for a portal every week, a documentation pipeline, a design handoff that always arrives in the wrong format — this is the workflow Zumkor collapses to one drag (it needs macOS 14 or later on an Apple silicon Mac — any M-series machine):

1. Open Zumkor and drag in the JPGs — or the whole folder, subfolders and all (“Look inside subfolders” picks up nested files).
2. Pick PNG as the output format.
3. (Optional) Add a resize preset in the same pass — “Email-friendly” caps the long edge at 1600 px, “Web small” at 1280 px — and flip on the personal-data strip if the files are headed somewhere public.
4. Click Convert and choose the output folder. Originals stay put.

Everything runs on-device and offline — no uploads, no web-tool file caps. Folder structure can be mirrored in the output, filename templates keep big batches organized, and the queue takes up to 2,000 files. The same drag handles the other directions and formats too: it reads HEIC, WebP, TIFF, GIF, BMP, and camera RAW alongside JPG, and writes PNG, JPG, HEIC, TIFF, WebP, and AVIF — so the week’s HEIC photos and WebP downloads go through the same app instead of a different trick per format.

Zumkor is free for 7 days, full-featured; after that it’s a one-time $19.99 purchase — buy once, keep it forever, no subscription. Fair is fair: for one image, Preview is free and already installed. The app earns its slot at folder scale and format variety.

Getting the output right

• Expect the file to grow. PNG stores photographic content losslessly, and photos are exactly what lossless compression handles worst — a 2 MB JPG routinely becomes an 8–15 MB PNG. That’s normal, not a mistake. If the size shocks you and the destination doesn’t strictly require PNG, reconsider whether you needed this conversion.
• Photos that need to stay small don’t want PNG. For photographic images where the goal is quality and size, modern formats do what PNG can’t: HEIC and WebP (both of which Zumkor writes) compress far smaller than PNG at visually identical quality. PNG’s niche is graphics, screenshots, transparency, and lossless pipelines — not holiday photos.
• Convert before you edit, not after. The point of PNG in an edit workflow is stopping generation loss. Convert first, then crop and annotate the PNG through as many rounds as needed. Converting after the fifth JPG re-save preserves the damage, not the image.
• Keep the JPG originals. Nothing is gained by deleting them — the PNGs contain no extra detail, and if a destination later wants JPG you’ll want the originals rather than round-tripping.
• Metadata survives conversion. Location and device info in a photo’s EXIF carries into the PNG unless you strip it — the Quick Action’s checkbox or Zumkor’s one-click strip handle that for anything leaving your machine.

The reverse trip, while you’re here

The other direction is the more common chore: PNG to JPG — shrinking multi-megabyte screenshots down to email-friendly JPGs — uses the same four tools with the formats swapped, plus a quality decision this direction doesn’t have. Between the two guides you have both lanes of the road covered. And if the images headed for a PNG-only destination are straight off an iPhone, they’re probably HEIC rather than JPG — HEIC to PNG covers that starting point with the same four tools.

Bottom line

• One or two images: Preview → File → Export → PNG (hold Option if PNG is hidden). Ten seconds, free.
• A folder, occasionally: Finder → right-click → Quick Actions → Convert Image → PNG.
• Part of a script: a sips -s format png loop.
• A recurring chore, big batches, or mixed formats: Zumkor — drag the folder, pick PNG once, convert offline in one pass, one-time $19.99.
• Before any of it: remember what the conversion can’t do — it won’t restore lost quality and it won’t create transparency. It stops future loss and satisfies PNG-only destinations; that’s the job, and it does it perfectly.

FAQ

How do I convert a JPG to PNG on a Mac without installing anything?

Open the JPG in Preview, choose File → Export, set Format to PNG, and save. For several files at once, select them in Finder, right-click, and choose Quick Actions → Convert Image with PNG as the format. Both tools are built into macOS and work completely offline.

Does converting JPG to PNG improve image quality?

No. PNG is lossless, so it preserves the JPG exactly as it is — compression artifacts included — but it cannot restore detail the JPG encode already discarded. What it does guarantee is that no further quality is lost from that point on, which is why editors and portals ask for PNG. Expect the PNG to be several times larger than the JPG.

Does converting JPG to PNG give the image a transparent background?

No. JPG has no transparency, so there is nothing for the PNG to inherit — the background pixels stay exactly as they are, just in a format that could hold transparency. Making a background actually transparent requires removing it in an editor (or macOS’s built-in Remove Background Quick Action); convert the result to PNG to keep it.