To save a screenshot as JPG on Windows or Mac, you can use built-in tools and a quick format change. On Windows, the Snipping Tool (Win+Shift+S) saves screenshots as PNG by default, but the Save As dialog lets you pick JPG. On a Mac, you can change the default screenshot format from PNG to JPG using a Terminal command, or export from Preview. This post walks through both methods and explains when JPG makes sense.

How Screenshots Behave by Default

Both Windows and Mac save screenshots as PNG files by default. PNG is a lossless format that keeps text and sharp edges crisp, ideal for capturing menus, error messages, or code. But PNG files can be larger than JPGs, especially for screenshots that include photos or gradients. JPG compresses the image, making the file much smaller. Many websites and upload forms also require JPG files. Here’s how to get JPG screenshots on each system.

On Windows: Using the Snipping Tool

Windows offers a built-in Snipping Tool that you can open with the keyboard shortcut Win+Shift+S. When you press those keys, the screen dims and a small toolbar appears at the top. You can capture a rectangular selection, a freeform shape, a window, or the full screen. After you take the snip, a notification appears. Click the notification to open the screenshot in the Snipping Tool editor.

By default, when you save the screenshot, the Snipping Tool saves it as a PNG file. To save as JPG:

  • Click the floppy-disk icon or press Ctrl+S to open the Save As dialog.
  • In the “Save as type” dropdown, select JPEG (*.jpg).
  • Choose a folder and filename, then click Save.

If you used the Print Screen key instead (which copies the full screen to the clipboard), you can paste the image into a program like Paint, then use File > Save As and pick JPEG from the format list. The same Save As dialog gives you the JPG option.

On Mac: Changing the Screenshot Format

Mac’s built-in screenshot shortcuts save images as PNG files. The two most common shortcuts are:

  • Cmd+Shift+3, captures the entire screen.
  • Cmd+Shift+4, captures a selected area.

To change the default format from PNG to JPG, you can use a Terminal command. Open the Terminal app (you can find it in Applications > Utilities) and type the following line, then press Enter:

defaults write com.apple.screencapture type jpg

After that, run this command to restart the system UI server so the change takes effect:

killall SystemUIServer

From that point on, any screenshot you take with Cmd+Shift+3 or Cmd+Shift+4 will be saved as a JPG file instead of PNG. If you ever want to switch back to PNG, repeat the same steps but replace jpg with png.

Using Preview to Export as JPG

If you prefer not to change the system-wide setting, you can convert an existing PNG screenshot to JPG using the Mac’s built-in Preview app. Open the screenshot in Preview, then go to File > Export. In the export dialog, choose JPEG from the format dropdown. Preview will save a new copy in JPG format while leaving the original PNG untouched. This method works well for one-off conversions.

When to Use JPG Vs. PNG

Choosing between JPG and PNG depends on what’s in the screenshot and what you plan to do with it.

  • Use PNG when the screenshot contains mostly text, UI elements, line art, or anything with sharp edges. PNG preserves those details perfectly because it’s a lossless format. It’s also a good choice if you need to edit the screenshot later and want to avoid quality loss from repeated saves.
  • Use JPG when the screenshot includes photos, gradients, or complex backgrounds. JPG compression can dramatically reduce file size, often by a significant amount, without a noticeable difference in quality for photographic content. Many online forms, email attachments, and content management systems also require JPG files. And if you’re taking a screenshot of a photo, JPG is the natural choice.

A Quick Online Option for Converting Screenshots

If you already have a screenshot saved as PNG and need a JPG copy, you can use a free online tool. For example, jpg.now is a free JPG converter that requires no sign-up. It accepts PNG files and converts them to JPG in seconds. The same site also handles conversions between many other image formats, including HEIC, WebP, PDF, and TIFF. It even includes utilities like a DPI/PPI converter, aspect ratio calculator, and image info/EXIF viewer. This can be handy if you need to batch convert or check image properties without installing software.