The quickest way to convert PNG to JPEG

You can convert a PNG image to a JPEG in seconds using free tools built into Windows or Mac, or through free online converters that require no download. The main difference between the two formats is that PNG files preserve transparency (see-through areas) while JPEG files do not — so if your PNG has a transparent background, converting it will fill that background with white or another solid color.

The method you choose depends on whether you have the image file on your computer or need to convert it online, and whether you care about keeping the transparency. For most people, using your computer's built-in tools is fastest and keeps your file private.

Key Takeaways

  • Windows users can right-click a PNG file and open it with Paint, then save it as a JPEG without installing anything.
  • Mac users can open a PNG in Preview, click File, then choose Export As and select JPEG from the format dropdown.
  • PNG files with transparent backgrounds will show a white background when converted to JPEG, since JPEG does not support transparency.
  • Free online converters like CloudConvert, Zamzar, or Convertio work from any device but upload your image to their servers.

Converting PNG to JPEG on Windows using Paint

Paint is a simple image editor built into every Windows computer. Open File Explorer, find your PNG file, right-click it, and select "Open with" then "Paint." The image will load in the Paint window.

Once the image is open, click "File" in the top left, then click "Save as." A dialog box will appear. In the "Save as type" dropdown at the bottom, select "JPEG picture (.jpg)." Type a new name for the file if you want to keep the original PNG, or use the same name to replace it. Click "Save" and Windows will convert the file.

Paint will not ask you about quality settings — it uses a standard compression level. If you need more control over how much the file is compressed, use the Mac method or an online converter instead.

Converting PNG to JPEG on Mac using Preview

Preview is the default image viewer on Mac and can also convert formats. Find your PNG file in Finder, double-click it to open it in Preview, then click "File" in the menu bar at the top of the screen.

Click "Export As" from the File menu. A save dialog will open. Look for the "Format" dropdown — it usually shows "PNG" by default. Click the dropdown and select "JPEG." You can type a new filename or keep the same name. Click "Save" and the conversion is complete.

Preview also shows a "Quality" slider before you save. Dragging it to the left makes the file smaller but blurrier; dragging it to the right keeps more detail but makes the file larger. For most photos, the middle setting works well.

Using free online converters

If you do not want to use your computer's built-in tools, free websites can convert PNG to JPEG from any device. CloudConvert, Zamzar, and Convertio are three popular options that work the same way: you upload your PNG file, select JPEG as the output format, and download the converted file.

The main trade-off is privacy — your image is uploaded to the converter's servers, processed there, and then deleted after a set time. Most of these services delete files within a few hours, but if your image contains sensitive information, using your computer's built-in tools is safer.

To use an online converter, visit the website, click the upload button, select your PNG file from your computer, wait for the conversion to finish (usually a few seconds), and click the download button. No account is required on most of these sites.

What happens to transparent backgrounds when you convert

PNG files can have transparent areas — parts of the image you can see through. JPEG files cannot store transparency, so when you convert, those transparent areas become solid white by default. If your PNG has a colored background that you want to preserve, the conversion will still turn it white unless you use an advanced tool.

If keeping the transparent background is important, do not convert to JPEG. Keep the file as PNG instead. JPEG is better for photographs and images with solid backgrounds; PNG is better for graphics, logos, and images where transparency matters.

Some online converters let you choose a background color before converting — if the default white does not work for you, check whether the converter offers this option before uploading.

File size and when to use each format

JPEG files are usually much smaller than PNG files, which is why many people convert. A photograph that is 2 MB as a PNG might be 200 KB as a JPEG. This matters if you are uploading images to a website, sending them by email, or storing many photos on a phone with limited space.

However, JPEG compression can make images look slightly blurry or grainy, especially if you compress them heavily. PNG keeps the image exactly as it is, but the file stays large. For photographs and realistic images, JPEG is the better choice. For graphics, text, and images where sharpness matters, PNG is usually better.

If you are converting for a specific purpose — uploading to a website, attaching to an email, or posting on social media — check whether that platform has format requirements. Many platforms accept both PNG and JPEG and will compress them anyway.

Frequently Asked Questions

Will converting PNG to JPEG make my image look worse?

It depends on the image and how much compression is used. Photographs usually look fine or nearly identical. Images with text, sharp lines, or graphics may look slightly blurry or have colored halos around edges. You can always convert a copy and compare the two files before deciding which to keep.

Can I convert JPEG back to PNG?

Yes, you can convert JPEG to PNG using the same methods — Paint on Windows, Preview on Mac, or an online converter. However, converting JPEG to PNG will not restore any detail lost during the original JPEG compression. The file will simply be larger without looking better.

What if my PNG file has a transparent background and I want to keep it?

Do not convert to JPEG. JPEG does not support transparency. If you need a smaller file size but want to keep transparency, keep the file as PNG or use a tool that can add a solid background color before converting.

Is it safe to use online converters with personal photos?

Most online converters delete files within hours, but your image is temporarily stored on their servers. If your photo contains sensitive information, using your computer's built-in tools is safer since the file never leaves your device.

Why is my converted JPEG file still large?

The image dimensions (width and height in pixels) matter more than the format. A 4000 × 3000 pixel photo will be large as either PNG or JPEG. To make the file smaller, you need to reduce the image size itself, not just change the format. Most image editors have a "resize" or "scale" option for this.