PNG to JPG: how to convert, what happens to transparency, and when to keep PNG

Convert PNG to JPG in your browser, many at once. What happens to transparent areas, which quality to pick, and when PNG is the better format.

Updated October 31, 2026

Short answer: open PNG to JPG, drop your .png files and download them as .jpg; JPG is already selected and quality is 90. JPG has no transparency, so transparent areas are filled with a solid colour, white by default, and you can pick another one. Convert photos and big screenshots to JPG; keep logos, icons and anything with a transparent background as PNG.

How to convert PNG to JPG on Nibbo

1. Open PNG to JPG. Under Convert to, JPG is already selected.
2. Check Background for transparency. It is white; click the colour box to choose another colour, for example the background colour of the page or slide the image goes on.
3. Leave Quality at 90 or move the slider (30 to 100). Lower means a smaller file.
4. Drop your PNG files on the page, or click to choose them. You can add many at once; they are converted one after another as soon as you add them.
5. Download each image with Download, or all of them with Download all as ZIP, which appears once more than one is ready. screenshot.png becomes screenshot.jpg.

The list shows the new size and dimensions of every file, and a Before / After slider lets you compare the result with the original. If you change the quality or the background colour after converting, press Convert to JPG to redo the whole batch. The pixel dimensions stay the same.

The images are decoded and encoded by your browser, on your device; nothing is uploaded. That matters for screenshots, which often show a chat, a bank app or an email.

What happens to transparency

PNG can store, for each pixel, how see-through it is (an alpha channel). JPG can’t: every pixel is a solid colour. So a converter has to decide what goes behind the transparent parts.

• Nibbo fills them with the colour under Background for transparency, white by default. It paints the colour first and draws the PNG on top, so half-transparent pixels, such as the soft edge of a logo or a shadow, blend smoothly into it.
• Why other converters give you a black background. Fully transparent pixels are usually stored as black with zero opacity. A tool that simply throws the alpha channel away shows that hidden black. Sometimes the hidden colour is something else entirely, such as leftovers of a removed background.

Match the fill to where the image will be shown. A logo with a white fill looks fine on a white page and like a white box on a dark one. If the image has to stay transparent, don’t convert it: keep the PNG, or convert it with PNG to WebP, since WebP keeps transparency and is usually smaller. Cut-outs from Remove background are PNG for exactly this reason.

PNG or JPG: which one to use

Convert to JPG when the PNG is really a photo (an export from an editor, a picture saved from a website, a phone screenshot of a photo) or when a form only accepts JPG/JPEG. The file often shrinks a lot.

Keep PNG for screenshots of text, code and spreadsheets, UI mock-ups, logos and charts. JPG adds faint noise around sharp edges, and for those images PNG is often not much bigger. If you need the opposite direction, use JPG to PNG, but note that it can’t undo JPG’s loss: you get a bigger file of the same picture.

Why screenshots are huge PNGs

Windows, macOS and iPhone save screenshots as PNG, and so do many Android phones. PNG is a good fit for text on a plain background, but a screenshot of a photo, a video frame or a game is full of fine colour variation that lossless compression can’t squeeze. A 4K screenshot holds about 8.3 million pixels, roughly 25 MB uncompressed; as PNG that can still be several megabytes, while a JPG at quality 85 to 90 is usually a fraction of that and looks the same on screen.

What to do with a screenshot that is too big:

• Mostly a photo or video frame: convert to JPG.
• Mostly text: keep PNG, or make it smaller in pixels with Resize image, which can save as JPG at the same time.
• Has to fit a limit such as 200 KB or 1 MB: use Compress image, which takes PNG directly and aims for an exact size.

Quality and file size

The Quality slider sets how much detail JPG may simplify:

• 90 (default): looks identical to the PNG at normal size. A good choice for anything you’ll keep.
• 75 to 85: noticeably smaller, still fine for photos you send or upload. Text in screenshots may start to look soft around the letters.
• Below 60: blocky areas and halos around edges. Only for tiny previews.
• 100: the biggest JPG, and still not lossless. If you need every pixel, keep the PNG.

Because JPG is lossy, convert once from the PNG instead of opening the JPG, editing it and saving it again and again; every save loses a little more.

A PNG made from a photo usually becomes a JPG many times smaller. A PNG that is a flat graphic, such as a logo or a screenshot of a text editor, may barely shrink, and occasionally the JPG comes out bigger. The size shown next to each file tells you before you download.

Metadata

The JPG carries no metadata from the PNG: no text fields, no creation software, nothing else that was stored in the file. The Keep EXIF metadata option applies to JPG to JPG only.

On Windows, Mac and phone

• Windows: in Paint, open the PNG and choose File › Save as › JPEG picture. Transparent areas are lost, there is no quality setting and no choice of background colour, and it works on one file at a time. For a folder of screenshots, drop them all on the browser page and take the ZIP.
• Mac: Preview opens the PNG; choose File › Export, set Format to JPEG and use the Quality slider. To make the Mac save new screenshots as JPG, run defaults write com.apple.screencapture type jpg in Terminal (use png to go back).
• iPhone: screenshots are PNG. The same converter works in Safari: tap the drop area, choose Photo Library, select the screenshots, then download the JPGs; they land in Files › Downloads. If an iPhone photo shows up as HEIC rather than PNG, see HEIC to JPG.
• Android: the converter works in Chrome. Some phones, Samsung among them, have a screenshot format setting where you can pick JPG.

Got a .avif or .webp file that won’t open instead? See AVIF to JPG.

Common problems

• The JPG has a white box around my logo. That’s the transparency fill. Choose the background colour of the place where the logo goes, or keep the PNG.
• Text looks blurry after converting. That’s JPG at work on sharp edges. Raise the quality to 95, or keep that screenshot as PNG.
• The file got bigger. It was a flat graphic that PNG compresses very well. Keep the PNG.
• A website still says “invalid format”. Check that the file ends in .jpg and wasn’t just renamed: renaming image.png to image.jpg doesn’t convert anything, and many upload checks look at the content.

FAQ

Is PNG to JPEG the same as PNG to JPG?

Yes. JPG and JPEG are the same format; .jpg is just the shorter extension. A form that asks for JPEG accepts a .jpg file.

Does converting PNG to JPG lose quality?

A little, because JPG is lossy, but at quality 90 you won’t see it on a photo at normal size. Screenshots of small text show it first. The resolution in pixels stays the same.

Why does my converted image have a black background?

The tool dropped the transparency without filling it, so the hidden colour of the transparent pixels shows. Nibbo fills transparent areas with white, or the colour you choose under Background for transparency.

Can I convert many PNG files to JPG at once?

Yes. Select or drop as many as you like; they are converted one by one and you can download them together as a ZIP.

Can I convert JPG back to PNG and get the original?

No. The details JPG removed are gone. Converting back gives a PNG of the JPG, usually larger and no sharper. Keep the original PNG if you might need it.