What happens when you convert JPG to PNG

Converting a JPG file to PNG changes the image format but not the picture itself. A JPG file uses compression that loses some image detail to keep file size small. A PNG file uses compression that keeps all the original detail but makes the file larger. When you convert from JPG to PNG, you get a file that preserves what the JPG already shows — you do not recover detail that the JPG compression removed.

The main reason to convert is that PNG supports transparency (see-through areas), while JPG does not. If you need a transparent background or plan to edit the image further, PNG is the better format. If you just need to store or share a photo, JPG usually stays smaller and works fine.

Key Takeaways

  • PNG files are larger than JPG files but support transparent backgrounds, which JPG cannot do.
  • You can convert using free online tools, your computer's built-in software, or image editing programs like Photoshop or GIMP.
  • The conversion process takes seconds and does not require any special knowledge or software purchase.
  • Converting does not recover image detail that was lost when the JPG was originally created.

Using free online conversion tools

Online converters are the fastest route if you do not want to install software. Sites like CloudConvert, Zamzar, and Online-Convert let you upload a JPG and download the PNG in seconds. You visit the website, select your JPG file, choose PNG as the output format, and click convert. Most tools are free for single images and do not require an account.

The tradeoff is that you are uploading your image to someone else's server. If the image contains private information or sensitive content, use a tool on your own computer instead. Also check the website's privacy policy — some free converters keep copies of uploaded files or use them for other purposes.

Converting on Windows using built-in tools

Windows does not have a single "convert" button, but you can save a JPG as PNG using Paint, which comes with every Windows computer. Open the JPG file in Paint (right-click the file, select "Open with," then choose Paint). Go to File > Save As, select PNG from the format dropdown, give the file a new name, and click Save.

Paint is simple but limited — it does not let you adjust quality or handle transparency. For more control, use the free program IrfanView, which you can download from irfanview.com. Open your JPG, go to File > Save As, choose PNG format, and save. IrfanView gives you options for compression level and other PNG settings.

Converting on Mac using built-in tools

The Preview app on Mac can convert JPG to PNG without installing anything. Open the JPG file in Preview (it usually opens by default when you double-click a JPG). Go to File > Export, change the format dropdown from JPEG to PNG, give the file a new name, and click Save.

Preview handles the conversion instantly and gives you basic options like quality level. If you need more control over transparency or compression, download the free program GIMP from gimp.org. GIMP works on both Mac and Windows and lets you edit the image before saving it as PNG.

Using image editing software

If you already own Photoshop, Affinity Photo, or another image editor, you can convert there. Open the JPG file, go to File > Export As (or Save As), select PNG from the format menu, and save. Most editors let you set the compression level — higher compression makes the file smaller but takes slightly longer to save.

GIMP is a free alternative that works the same way. Open the JPG, go to File > Export As, choose PNG, and click Export. GIMP will show you options for interlacing and compression. For most photos, the default settings work fine.

Batch converting multiple JPG files at once

If you have many JPG files to convert, doing them one at a time is slow. IrfanView (Windows) and GIMP (Mac and Windows) both have batch conversion features. In IrfanView, go to File > Batch Conversion, select your JPG files, choose PNG as the output format, and run the batch. GIMP uses Filters > Batch Process, though the steps vary depending on your version.

Online tools like CloudConvert also handle batch uploads — you can select multiple files at once and convert them all in one go. This saves time if you have 10 or more files to convert.

Understanding PNG file size and quality settings

PNG files are usually 2 to 5 times larger than the same image saved as JPG, because PNG compression keeps all the detail. When you convert a JPG to PNG, the PNG file will be bigger than the original JPG, but it will not be bigger than the original image was before it became a JPG.

Most conversion tools let you choose a compression level. Higher compression makes the file smaller but takes a few seconds longer to save. For photos, compression level 6 or 7 is standard and balances file size with speed. For images with text or sharp edges, higher compression (8 or 9) keeps the detail clearer.

Frequently Asked Questions

Will converting JPG to PNG make the image look better?

No. PNG preserves what the JPG already shows, but it cannot recover detail that was lost when the JPG was first created. If the original JPG was low quality, the PNG will be the same quality, just in a different format. The PNG file will be larger, not better-looking.

Can I convert PNG back to JPG?

Yes, using the same tools. Open the PNG file, go to File > Save As or Export As, select JPG format, and save. Keep in mind that JPG compression will reduce quality slightly, so you lose a small amount of detail in the conversion back. For this reason, keep the PNG as your main file if you might need to edit it later.

Do I need to buy software to convert JPG to PNG?

No. Windows Paint, Mac Preview, and free tools like IrfanView and GIMP all convert JPG to PNG at no cost. Online converters are also free for single images. You only need to buy software if you want advanced editing features beyond simple format conversion.

What is the difference between PNG-8 and PNG-24?

PNG-8 uses 256 colors and creates smaller files, while PNG-24 uses millions of colors and creates larger files. Most conversion tools default to PNG-24, which is fine for photos and detailed images. PNG-8 works better for simple graphics with solid colors. You can usually choose which one during conversion.

Can I convert a JPG to PNG on my phone?

Yes. On iPhone, use the free app Image Converter or Convertio. On Android, try CloudConvert's app or Image Converter. Upload your JPG, select PNG as the output format, and download the converted file. The process is the same as on a computer, just on a smaller screen.